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

…a to 2.18.1 (#228)

- [ ] Regenerate this pull request now.

PiperOrigin-RevId: 450543911

Source-Link: googleapis/googleapis@5528344

Source-Link: googleapis/googleapis-gen@9f6775c
Copy-Tag: eyJwIjoiLmdpdGh1Yi8uT3dsQm90LnlhbWwiLCJoIjoiOWY2Nzc1Y2FiMTk1ODk4MmI4ODk2N2E0M2U1ZTgwNmFmMGYxMzVkYiJ9

java-gsuite-addons/google-cloud-gsuite-addons/src/main/java/com/google/cloud/gsuiteaddons/v1/GSuiteAddOnsClient.java

@@ -18,7 +18,6 @@
 
 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.paging.AbstractFixedSizeCollection;
 import com.google.api.gax.paging.AbstractPage;
@@ -143,7 +142,6 @@ public static final GSuiteAddOnsClient create(GSuiteAddOnsSettings settings) thr
    * Constructs an instance of GSuiteAddOnsClient, using the given stub for making calls. This is
    * for advanced usage - prefer using create(GSuiteAddOnsSettings).
    */
-  @BetaApi("A restructuring of stub classes is planned, so this may break in the future")
   public static final GSuiteAddOnsClient create(GSuiteAddOnsStub stub) {
     return new GSuiteAddOnsClient(stub);
   }
@@ -158,7 +156,6 @@ protected GSuiteAddOnsClient(GSuiteAddOnsSettings settings) throws IOException {
     this.stub = ((GSuiteAddOnsStubSettings) settings.getStubSettings()).createStub();
   }
 
-  @BetaApi("A restructuring of stub classes is planned, so this may break in the future")
   protected GSuiteAddOnsClient(GSuiteAddOnsStub stub) {
     this.settings = null;
     this.stub = stub;
@@ -168,7 +165,6 @@ public final GSuiteAddOnsSettings getSettings() {
     return settings;
   }
 
-  @BetaApi("A restructuring of stub classes is planned, so this may break in the future")
   public GSuiteAddOnsStub getStub() {
     return stub;
   }

java-gsuite-addons/google-cloud-gsuite-addons/src/main/java/com/google/cloud/gsuiteaddons/v1/stub/GSuiteAddOnsStubSettings.java

@@ -218,7 +218,6 @@ public UnaryCallSettings<GetInstallStatusRequest, InstallStatus> getInstallStatu
     return getInstallStatusSettings;
   }
 
-  @BetaApi("A restructuring of stub classes is planned, so this may break in the future")
   public GSuiteAddOnsStub createStub() throws IOException {
     if (getTransportChannelProvider()
         .getTransportName()