fix(o11y): remove gpc.client.language attribute (#12621)

Author: diegomarquezp

sdk-platform-java/gax-java/gax/src/main/java/com/google/api/gax/tracing/SpanTracer.java

@@ -45,9 +45,6 @@
 @BetaApi
 @InternalApi
 public class SpanTracer implements ApiTracer {
-  public static final String LANGUAGE_ATTRIBUTE = "gcp.client.language";
-
-  public static final String DEFAULT_LANGUAGE = "Java";
 
   static final String CONTENT_LENGTH_KEY = "Content-Length";
 
@@ -103,7 +100,6 @@ private static String resolveAttemptSpanName(ApiTracerContext apiTracerContext)
   }
 
   private void buildAttributes() {
-    this.attemptAttributes.put(LANGUAGE_ATTRIBUTE, DEFAULT_LANGUAGE);
     this.attemptAttributes.putAll(this.apiTracerContext.getAttemptAttributes());
   }
 

sdk-platform-java/gax-java/gax/src/test/java/com/google/api/gax/tracing/SpanTracerTest.java

@@ -84,19 +84,6 @@ void testAttemptLifecycle_startsAndEndsAttemptSpan() {
     verify(span).end();
   }
 
-  @Test
-  void testAttemptStarted_includesLanguageAttribute() {
-    spanTracer.attemptStarted(new Object(), 1);
-
-    ArgumentCaptor<Attributes> attributesCaptor = ArgumentCaptor.forClass(Attributes.class);
-    verify(spanBuilder).setAllAttributes(attributesCaptor.capture());
-
-    assertThat(attributesCaptor.getValue().asMap())
-        .containsEntry(
-            io.opentelemetry.api.common.AttributeKey.stringKey(SpanTracer.LANGUAGE_ATTRIBUTE),
-            SpanTracer.DEFAULT_LANGUAGE);
-  }
-
   @Test
   void testAttemptSucceeded_grpc() {
     ApiTracerContext context =

sdk-platform-java/java-showcase/gapic-showcase/src/test/java/com/google/showcase/v1beta1/it/ITOtelTracing.java

@@ -42,7 +42,6 @@
 import com.google.api.gax.rpc.TransportChannelProvider;
 import com.google.api.gax.rpc.UnavailableException;
 import com.google.api.gax.tracing.ObservabilityAttributes;
-import com.google.api.gax.tracing.SpanTracer;
 import com.google.api.gax.tracing.SpanTracerFactory;
 import com.google.common.collect.ImmutableList;
 import com.google.protobuf.InvalidProtocolBufferException;
@@ -134,11 +133,6 @@ void testTracing_successfulEcho_grpc() throws Exception {
               .findFirst()
               .orElseThrow(() -> new AssertionError("Incorrect span name"));
       assertThat(attemptSpan.getKind()).isEqualTo(SpanKind.CLIENT);
-      assertThat(
-              attemptSpan
-                  .getAttributes()
-                  .get(AttributeKey.stringKey(SpanTracer.LANGUAGE_ATTRIBUTE)))
-          .isEqualTo(SpanTracer.DEFAULT_LANGUAGE);
       assertThat(
               attemptSpan
                   .getAttributes()
@@ -220,11 +214,6 @@ void testTracing_successfulEcho_httpjson() throws Exception {
               .orElseThrow(
                   () -> new AssertionError("Attempt span 'POST v1beta1/echo:echo' not found"));
       assertThat(attemptSpan.getKind()).isEqualTo(SpanKind.CLIENT);
-      assertThat(
-              attemptSpan
-                  .getAttributes()
-                  .get(AttributeKey.stringKey(SpanTracer.LANGUAGE_ATTRIBUTE)))
-          .isEqualTo(SpanTracer.DEFAULT_LANGUAGE);
       assertThat(
               attemptSpan
                   .getAttributes()