fix: suppress warnings in generated projects for non-idiomatic durations (googleapis#4119)

Removes compiler warnings like
```
 [CanonicalDuration] Duration can be expressed more clearly with different units
    (see https://errorprone.info/bugpattern/CanonicalDuration)
  Did you mean '.setMaxRetryDelayDuration(Duration.ofSeconds(45))'?
```
from generated clients

---------

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

Author: igorbernstein2

gapic-generator-java/src/main/java/com/google/api/generator/gapic/composer/common/AbstractServiceStubSettingsClassComposer.java

@@ -424,6 +424,13 @@ private List<AnnotationNode> createClassAnnotations(Service service) {
             .setType(FIXED_TYPESTORE.get("Generated"))
             .setDescription("by gapic-generator-java")
             .build());
+
+    // Suppress the error-prone CanonicalDuration warning in generated code.
+    annotations.add(
+        AnnotationNode.builder()
+            .setType(FIXED_TYPESTORE.get("SuppressWarnings"))
+            .setDescription("CanonicalDuration")
+            .build());
     return annotations;
   }
 
@@ -2188,6 +2195,7 @@ private static TypeStore createStaticTypes() {
             StatusCode.class,
             StreamingCallSettings.class,
             StubSettings.class,
+            SuppressWarnings.class,
             TransportChannelProvider.class,
             UnaryCallSettings.class,
             UnaryCallable.class);

gapic-generator-java/src/test/java/com/google/api/generator/gapic/composer/grpc/goldens/ApiVersionTestingStubSettings.golden

@@ -77,6 +77,7 @@ import javax.annotation.Generated;
  * retries.
  */
 @Generated("by gapic-generator-java")
+@SuppressWarnings("CanonicalDuration")
 public class EchoWithVersionStubSettings extends StubSettings<EchoWithVersionStubSettings> {
   /** The default scopes of the service. */
   private static final ImmutableList<String> DEFAULT_SERVICE_SCOPES =

gapic-generator-java/src/test/java/com/google/api/generator/gapic/composer/grpc/goldens/DeprecatedServiceStubSettings.golden

@@ -82,6 +82,7 @@ import javax.annotation.Generated;
  */
 @Deprecated
 @Generated("by gapic-generator-java")
+@SuppressWarnings("CanonicalDuration")
 public class DeprecatedServiceStubSettings extends StubSettings<DeprecatedServiceStubSettings> {
   /** The default scopes of the service. */
   private static final ImmutableList<String> DEFAULT_SERVICE_SCOPES =

gapic-generator-java/src/test/java/com/google/api/generator/gapic/composer/grpc/goldens/EchoServiceSelectiveGapicStubSettings.golden

@@ -84,6 +84,7 @@ import javax.annotation.Generated;
  */
 @BetaApi
 @Generated("by gapic-generator-java")
+@SuppressWarnings("CanonicalDuration")
 public class EchoServiceShouldGeneratePartialUsualStubSettings
     extends StubSettings<EchoServiceShouldGeneratePartialUsualStubSettings> {
   /** The default scopes of the service. */

gapic-generator-java/src/test/java/com/google/api/generator/gapic/composer/grpc/goldens/EchoStubSettings.golden

@@ -131,6 +131,7 @@ import javax.annotation.Generated;
  */
 @BetaApi
 @Generated("by gapic-generator-java")
+@SuppressWarnings("CanonicalDuration")
 public class EchoStubSettings extends StubSettings<EchoStubSettings> {
   /** The default scopes of the service. */
   private static final ImmutableList<String> DEFAULT_SERVICE_SCOPES =

gapic-generator-java/src/test/java/com/google/api/generator/gapic/composer/grpc/goldens/JobServiceStubSettings.golden

@@ -87,6 +87,7 @@ import javax.annotation.Generated;
  * retries.
  */
 @Generated("by gapic-generator-java")
+@SuppressWarnings("CanonicalDuration")
 public class JobServiceStubSettings extends StubSettings<JobServiceStubSettings> {
   /** The default scopes of the service. */
   private static final ImmutableList<String> DEFAULT_SERVICE_SCOPES =

gapic-generator-java/src/test/java/com/google/api/generator/gapic/composer/grpc/goldens/LoggingServiceV2StubSettings.golden

@@ -111,6 +111,7 @@ import javax.annotation.Generated;
  * retries.
  */
 @Generated("by gapic-generator-java")
+@SuppressWarnings("CanonicalDuration")
 public class LoggingServiceV2StubSettings extends StubSettings<LoggingServiceV2StubSettings> {
   /** The default scopes of the service. */
   private static final ImmutableList<String> DEFAULT_SERVICE_SCOPES =

gapic-generator-java/src/test/java/com/google/api/generator/gapic/composer/grpc/goldens/PublisherStubSettings.golden

@@ -111,6 +111,7 @@ import javax.annotation.Generated;
  * retries.
  */
 @Generated("by gapic-generator-java")
+@SuppressWarnings("CanonicalDuration")
 public class PublisherStubSettings extends StubSettings<PublisherStubSettings> {
   /** The default scopes of the service. */
   private static final ImmutableList<String> DEFAULT_SERVICE_SCOPES =

gapic-generator-java/src/test/java/com/google/api/generator/gapic/composer/grpcrest/goldens/EchoStubSettings.golden

@@ -135,6 +135,7 @@ import javax.annotation.Generated;
  */
 @BetaApi
 @Generated("by gapic-generator-java")
+@SuppressWarnings("CanonicalDuration")
 public class EchoStubSettings extends StubSettings<EchoStubSettings> {
   /** The default scopes of the service. */
   private static final ImmutableList<String> DEFAULT_SERVICE_SCOPES =

gapic-generator-java/src/test/java/com/google/api/generator/gapic/composer/grpcrest/goldens/WickedStubSettings.golden

@@ -79,6 +79,7 @@ import javax.annotation.Generated;
  */
 @BetaApi
 @Generated("by gapic-generator-java")
+@SuppressWarnings("CanonicalDuration")
 public class WickedStubSettings extends StubSettings<WickedStubSettings> {
   /** The default scopes of the service. */
   private static final ImmutableList<String> DEFAULT_SERVICE_SCOPES =