Add IAP support to compute_region_backend_service

[upodroid]

Fixes: hashicorp/terraform-provider-google#9279

If this PR is for Terraform, I acknowledge that I have:

• Searched through the issue tracker for an open issue that this either resolves or contributes to, commented on it to claim it, and written "fixes {url}" or "part of {url}" in this PR description. If there were no relevant open issues, I opened one and commented that I would like to work on it (not necessary for very small changes).
• Generated Terraform, and ran make test and make lint to ensure it passes unit and linter tests.
• Ensured that all new fields I added that can be set by a user appear in at least one example (for generated resources) or third_party test (for handwritten resources or update tests).
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• Read the Release Notes Guide before writing my release note below.

Release Note Template for Downstream PRs (will be copied)

compute: added `iap` fields to `google_compute_region_backend_service`

[modular-magician]

Hello! I am a robot who works on Magic Modules PRs.

I have detected that you are a community contributor, so your PR will be assigned to someone with a commit-bit on this repo for initial review.

Thanks for your contribution! A human will be with you soon.

@melinath, please review this PR or find an appropriate assignee.

[modular-magician]

Hi! I'm the modular magician. Your PR generated some diffs in downstreams - here they are.

Diff report:

Terraform GA: Diff ( 3 files changed, 241 insertions(+))
Terraform Beta: Diff ( 3 files changed, 241 insertions(+))
TF Conversion: Diff ( 1 file changed, 71 insertions(+))

[melinath]

/gcbrun

[modular-magician]

Hi! I'm the modular magician. Your PR generated some diffs in downstreams - here they are.

Diff report:

Terraform GA: Diff ( 3 files changed, 241 insertions(+))
Terraform Beta: Diff ( 4 files changed, 245 insertions(+))
TF Conversion: Diff ( 1 file changed, 71 insertions(+))

[melinath]

It looks like this is just copying the IAP support from BackendService to RegionBackendService; having consistency across those resources is definitely good! Assuming the tests pass, I'll approve & merge.

[modular-magician]

I have triggered VCR tests in RECORDING mode for the following tests that failed during VCR: TestAccApiGatewayApi_apigatewayApiBasicExample|TestAccApiGatewayApi_apigatewayApiFullExample|TestAccApiGatewayGateway_apigatewayGatewayFullExample|TestAccAssuredWorkloadsWorkload_BasicHandWritten|TestAccArtifactRegistryRepository_artifactRegistryRepositoryBasicExample|TestAccArtifactRegistryRepository_artifactRegistryRepositoryCmekExample|TestAccAssuredWorkloadsWorkload_FullHandWritten|TestAccArtifactRegistryRepository_artifactRegistryRepositoryIamExample|TestAccComposerEnvironment_update|TestAccComposerEnvironment_withSoftwareConfig|TestAccComputeAutoscaler_autoscalerSingleInstanceExample|TestAccComputeBackendService_backendServiceNetworkEndpointExample|TestAccComputeBackendService_backendServiceTrafficDirectorRoundRobinExample|TestAccComputeBackendService_backendServiceTrafficDirectorRingHashExample|TestAccComputeForwardingRule_internalTcpUdpLbWithMigBackendExample|TestAccComputeForwardingRule_internalHttpLbWithMigBackendExample|TestAccComputeForwardingRule_forwardingRuleExternallbExample|TestAccComputeForwardingRule_forwardingRuleGlobalInternallbExample|TestAccComputeForwardingRule_forwardingRuleL3DefaultExample|TestAccComputeForwardingRule_forwardingRuleInternallbExample|TestAccComputeForwardingRule_forwardingRuleHttpLbExample|TestAccComputeGlobalAddress_globalAddressPrivateServicesConnectExample|TestAccComputeGlobalForwardingRule_globalForwardingRuleInternalExample|TestAccComputeGlobalForwardingRule_privateServiceConnectGoogleApisExample|TestAccComputeHealthCheck_healthCheckWithLoggingExample|TestAccComputeMachineImage_machineImageBasicExample|TestAccComputeMachineImage_computeMachineImageKmsExample|TestAccComputePacketMirroring_computePacketMirroringFullExample|TestAccComputeRegionBackendService_regionBackendServiceBasicExample|TestAccComputeRegionBackendService_regionBackendServiceCacheExample|TestAccComputeRegionBackendService_regionBackendServiceIlbRoundRobinExample|TestAccComputeRegionBackendService_regionBackendServiceExternalExample|TestAccComputeRegionBackendService_regionBackendServiceIlbRingHashExample|TestAccComputeRegionBackendService_basic|TestAccComputeRegionBackendService_withBackendAndIAP|TestAccComputeRegionBackendService_regionBackendServiceBalancingModeExample|TestAccComputeRegionBackendService_withBackendInternal|TestAccComputeRegionBackendService_withBackendMultiNic|TestAccComputeRegionBackendService_ilbUpdateBasic|TestAccComputeRegionBackendService_ilbUpdateFull|TestAccComputeRegionBackendService_withConnectionDrainingAndUpdate|TestAccComputeRegionBackendService_withBackendInternalManaged|TestAccComputeRegionHealthCheck_regionHealthCheckHttpLogsExample|TestAccComputeRegionTargetHttpProxy_regionTargetHttpProxyBasicExample|TestAccComputeRegionTargetHttpsProxy_regionTargetHttpsProxyBasicExample|TestAccComputeRegionTargetHttpProxy_update|TestAccComputeRegionTargetHttpsProxy_update|TestAccComputeRegionUrlMap_regionUrlMapBasicExample|TestAccComputeRegionUrlMap_regionUrlMapL7IlbPathPartialExample|TestAccComputeRegionUrlMap_regionUrlMapL7IlbRoutePartialExample|TestAccComputeRegionUrlMap_regionUrlMapL7IlbRouteExample|TestAccComputeRegionUrlMap_update_path_matcher|TestAccComputeRegionUrlMap_regionUrlMapL7IlbPathExample|TestAccComputeRegionUrlMap_advanced|TestAccComputeRegionUrlMap_noPathRulesWithUpdate|TestAccComputeRegionUrlMap_ilbPathUpdate|TestAccComputeRegionUrlMap_ilbRouteUpdate|TestAccComputeRoute_routeIlbExample|TestAccComputeRouterPeer_basic|TestAccComputeRouterPeer_enable|TestAccComputeRouterNat_withManualIpAndSubnetConfiguration|TestAccComputeRouterNat_withDisabledIndependentEndpointMapping|TestAccComputeRouterNat_withNatIpsAndDrainNatIps|TestAccComputeServiceAttachment_serviceAttachmentBasicExample|TestAccComputeServiceAttachment_serviceAttachmentExplicitProjectsExample|TestAccComputeSubnetwork_subnetworkInternalL7lbExample|TestAccComputeTargetInstance_targetInstanceCustomNetworkExample|TestAccComputeVpnTunnel_vpnTunnelBetaExample|TestAccDataCatalogPolicyTag_dataCatalogTaxonomiesPolicyTagBasicExample|TestAccDataCatalogPolicyTag_dataCatalogTaxonomiesPolicyTagChildPoliciesExample|TestAccDataCatalogTaxonomy_dataCatalogTaxonomyBasicExample|TestAccDataFusionInstance_dataFusionInstanceFullExample|TestAccDataFusionInstance_dataFusionInstanceBasicExample|TestAccDataprocMetastoreService_dataprocMetastoreServiceBasicExample|TestAccDNSManagedZone_dnsManagedZoneServiceDirectoryExample|TestAccFilestoreInstance_filestoreInstanceFullExample|TestAccHealthcareDicomStore_healthcareDicomStoreBqStreamExample|TestAccHealthcareHl7V2Store_healthcareHl7V2StoreParserConfigExample|TestAccHealthcareHl7V2Store_healthcareHl7V2StoreUnschematizedExample|TestAccIAMBetaWorkloadIdentityPool_iamWorkloadIdentityPoolBasicExample|TestAccIAMBetaWorkloadIdentityPool_iamWorkloadIdentityPoolFullExample|TestAccIAMBetaWorkloadIdentityPoolProvider_iamWorkloadIdentityPoolProviderAwsBasicExample|TestAccIAMBetaWorkloadIdentityPoolProvider_iamWorkloadIdentityPoolProviderAwsFullExample|TestAccIAMBetaWorkloadIdentityPoolProvider_iamWorkloadIdentityPoolProviderOidcBasicExample|TestAccIAMBetaWorkloadIdentityPoolProvider_iamWorkloadIdentityPoolProviderOidcFullExample|TestAccPrivatecaCaPool_privatecaCapoolEmptyBaseline|TestAccSecurityScannerScanConfig_scanConfigBasicExample|TestAccServiceDirectoryNamespace_serviceDirectoryNamespaceBasicExample|TestAccServiceDirectoryEndpoint_serviceDirectoryEndpointBasicExample|TestAccServiceDirectoryService_serviceDirectoryServiceBasicExample|TestAccServiceUsageConsumerQuotaOverride_consumerQuotaOverrideZeroValueExample|TestAccServiceUsageConsumerQuotaOverride_consumerQuotaOverrideExample|TestAccServiceUsageConsumerQuotaOverride_regionConsumerQuotaOverrideExample You can view the result here: https://ci-oss.hashicorp.engineering/viewQueued.html?itemId=204703

[melinath]

LGTM

[melinath]

Failures look unrelated