resource/aws_db_instance: Prevent error when restoring database from snapshot with tagging enabled

[bflad]

Fixes #5385
Fixes #5360

Changes proposed in this pull request:

• Add initial acceptance testing for snapshot_identifier
• Only tag during actual resource update (due to API restrictions, update is called by snapshot_identifier when using custom VPCs and resetting password)

Before code change:

=== RUN   TestAccAWSDBInstance_SnapshotIdentifier_VpcSecurityGroupIds_Tags
--- FAIL: TestAccAWSDBInstance_SnapshotIdentifier_VpcSecurityGroupIds_Tags (785.49s)
	testing.go:518: Step 0 error: Error applying: 1 error(s) occurred:

		* aws_db_instance.test: 1 error(s) occurred:

		* aws_db_instance.test: InvalidParameterValue: The parameter ResourceName must be provided and must not be blank.
			status code: 400, request id: f0a46ea8-48d5-49ee-bcf7-17eb15ce4523

Output from acceptance testing:

25 tests passed (all tests)
=== RUN   TestAccAWSDBInstance_iamAuth
--- PASS: TestAccAWSDBInstance_iamAuth (473.93s)
=== RUN   TestAccAWSDBInstance_optionGroup
--- PASS: TestAccAWSDBInstance_optionGroup (494.32s)
=== RUN   TestAccAWSDBInstance_importBasic
--- PASS: TestAccAWSDBInstance_importBasic (494.67s)
=== RUN   TestAccAWSDBInstance_kmsKey
--- PASS: TestAccAWSDBInstance_kmsKey (533.59s)
=== RUN   TestAccAWSDBInstance_generatedName
--- PASS: TestAccAWSDBInstance_generatedName (544.94s)
=== RUN   TestAccAWSDBInstance_namePrefix
--- PASS: TestAccAWSDBInstance_namePrefix (595.57s)
=== RUN   TestAccAWSDBInstance_basic
--- PASS: TestAccAWSDBInstance_basic (605.42s)
=== RUN   TestAccAWSDBInstance_separate_iops_update
--- PASS: TestAccAWSDBInstance_separate_iops_update (619.22s)
=== RUN   TestAccAWSDBInstance_portUpdate
--- PASS: TestAccAWSDBInstance_portUpdate (671.05s)
=== RUN   TestAccAWSDBInstance_s3
--- PASS: TestAccAWSDBInstance_s3 (759.89s)
=== RUN   TestAccAWSDBInstance_enhancedMonitoring
--- PASS: TestAccAWSDBInstance_enhancedMonitoring (761.11s)
=== RUN   TestAccAWSDBInstance_subnetGroup
--- PASS: TestAccAWSDBInstance_subnetGroup (807.72s)
=== RUN   TestAccAWSDBInstance_noSnapshot
--- PASS: TestAccAWSDBInstance_noSnapshot (856.75s)
=== RUN   TestAccAWSDBInstance_diffSuppressInitialState
--- PASS: TestAccAWSDBInstance_diffSuppressInitialState (390.99s)
=== RUN   TestAccAWSDBInstance_ec2Classic
--- PASS: TestAccAWSDBInstance_ec2Classic (400.57s)
=== RUN   TestAccAWSDBInstance_snapshot
--- PASS: TestAccAWSDBInstance_snapshot (958.45s)
=== RUN   TestAccAWSDBInstance_cloudwatchLogsExportConfiguration
--- PASS: TestAccAWSDBInstance_cloudwatchLogsExportConfiguration (445.85s)
=== RUN   TestAccAWSDBInstance_MinorVersion
--- PASS: TestAccAWSDBInstance_MinorVersion (512.17s)
=== RUN   TestAccAWSDBInstance_cloudwatchLogsExportConfigurationUpdate
--- PASS: TestAccAWSDBInstance_cloudwatchLogsExportConfigurationUpdate (533.79s)
=== RUN   TestAccAWSDBInstance_SnapshotIdentifier
--- PASS: TestAccAWSDBInstance_SnapshotIdentifier (1116.39s)
=== RUN   TestAccAWSDBInstance_SnapshotIdentifier_Tags
--- PASS: TestAccAWSDBInstance_SnapshotIdentifier_Tags (1121.49s)
=== RUN   TestAccAWSDBInstance_SnapshotIdentifier_VpcSecurityGroupIds_Tags
--- PASS: TestAccAWSDBInstance_SnapshotIdentifier_VpcSecurityGroupIds_Tags (1222.80s)
=== RUN   TestAccAWSDBInstance_MSSQL_TZ
--- PASS: TestAccAWSDBInstance_MSSQL_TZ (1545.36s)
=== RUN   TestAccAWSDBInstance_replica
--- PASS: TestAccAWSDBInstance_replica (1549.86s)
=== RUN   TestAccAWSDBInstance_SnapshotIdentifier_VpcSecurityGroupIds
--- PASS: TestAccAWSDBInstance_SnapshotIdentifier_VpcSecurityGroupIds (2154.55s)

[catsby]

LGMT 👍

[bflad]

This has been released in version 1.30.0 of the AWS provider. Please see the Terraform documentation on provider versioning or reach out if you need any assistance upgrading.

[ghost]

I'm going to lock this issue because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.

If you feel this issue should be reopened, we encourage creating a new issue linking back to this one for added context. Thanks!