chore(deps): upgrade gapic-generator-java to 2.8.0 and update gax-jav…

…a to 2.18.1 (#244)

- [ ] Regenerate this pull request now.

PiperOrigin-RevId: 450543911

Source-Link: googleapis/googleapis@5528344

Source-Link: https://github.com/googleapis/googleapis-gen/commit/9f6775cab1958982b88967a43e5e806af0f135db
Copy-Tag: eyJwIjoiLmdpdGh1Yi8uT3dsQm90LnlhbWwiLCJoIjoiOWY2Nzc1Y2FiMTk1ODk4MmI4ODk2N2E0M2U1ZTgwNmFmMGYxMzVkYiJ9

java-service-management/google-cloud-service-management/src/main/java/com/google/cloud/api/servicemanagement/v1/ServiceManagerClient.java

@@ -19,7 +19,6 @@
 import com.google.api.Service;
 import com.google.api.core.ApiFuture;
 import com.google.api.core.ApiFutures;
-import com.google.api.core.BetaApi;
 import com.google.api.gax.core.BackgroundResource;
 import com.google.api.gax.longrunning.OperationFuture;
 import com.google.api.gax.paging.AbstractFixedSizeCollection;
@@ -154,7 +153,6 @@ public static final ServiceManagerClient create(ServiceManagerSettings settings)
    * Constructs an instance of ServiceManagerClient, using the given stub for making calls. This is
    * for advanced usage - prefer using create(ServiceManagerSettings).
    */
-  @BetaApi("A restructuring of stub classes is planned, so this may break in the future")
   public static final ServiceManagerClient create(ServiceManagerStub stub) {
     return new ServiceManagerClient(stub);
   }
@@ -170,7 +168,6 @@ protected ServiceManagerClient(ServiceManagerSettings settings) throws IOExcepti
     this.operationsClient = OperationsClient.create(this.stub.getOperationsStub());
   }
 
-  @BetaApi("A restructuring of stub classes is planned, so this may break in the future")
   protected ServiceManagerClient(ServiceManagerStub stub) {
     this.settings = null;
     this.stub = stub;
@@ -181,7 +178,6 @@ public final ServiceManagerSettings getSettings() {
     return settings;
   }
 
-  @BetaApi("A restructuring of stub classes is planned, so this may break in the future")
   public ServiceManagerStub getStub() {
     return stub;
   }

java-service-management/google-cloud-service-management/src/main/java/com/google/cloud/api/servicemanagement/v1/stub/ServiceManagerStubSettings.java

@@ -438,7 +438,6 @@ public UnaryCallSettings<CreateServiceRolloutRequest, Operation> createServiceRo
     return generateConfigReportSettings;
   }
 
-  @BetaApi("A restructuring of stub classes is planned, so this may break in the future")
   public ServiceManagerStub createStub() throws IOException {
     if (getTransportChannelProvider()
         .getTransportName()