test(gax-grpc): run the full unit test suite in CI (#14573)

Fixes #14572.

The Surefire `<test>` value in gax-grpc ended with an entry without a
`!`. Surefire treats that as an inclusion pattern, so only
`InstantiatingGrpcChannelProviderTest#testLogDirectPathMisconfigWrongCredential`
ran in CI.

- **`gax-grpc/pom.xml`:** drop the stray inclusion and keep both
existing exclusions.
-
**`InstantiatingGrpcChannelProviderTest#testLogDirectPathMisconfigWrongCredential`:**
set `.setEnvProvider(name -> null)`, so the test no longer depends on
the machine's `GOOGLE_CLOUD_DISABLE_DIRECT_PATH`. With it set to `true`,
the test fails because the provider takes the "DirectPath disabled"
branch. It passed on GitHub runners only because the variable isn't set
there.

**Testing:** `mvn test -pl gax-grpc` now runs 209 tests, all passing,
locally on JDK 21. Before, it ran 1.

Author: macastelaz

sdk-platform-java/gax-java/gax-grpc/pom.xml

@@ -158,7 +158,7 @@
         <artifactId>maven-surefire-plugin</artifactId>
         <configuration>
           <!-- These tests require an Env Var to be set. Use -PenvVarTest to ONLY run these tests -->
-          <test>!InstantiatingGrpcChannelProviderTest#testLogDirectPathMisconfig_AttemptDirectPathNotSetAndAttemptDirectPathXdsSetViaEnv_warns,!InstantiatingGrpcChannelProviderTest#canUseDirectPath_directPathEnvVarNotSet_attemptDirectPathIsTrue,InstantiatingGrpcChannelProviderTest#testLogDirectPathMisconfigWrongCredential</test>
+          <test>!InstantiatingGrpcChannelProviderTest#testLogDirectPathMisconfig_AttemptDirectPathNotSetAndAttemptDirectPathXdsSetViaEnv_warns,!InstantiatingGrpcChannelProviderTest#canUseDirectPath_directPathEnvVarNotSet_attemptDirectPathIsTrue</test>
           <!-- <test>!InstantiatingGrpcChannelProviderTest#testLogDirectPathMisconfig_AttemptDirectPathNotSetAndAttemptDirectPathXdsSetViaEnv_warns</test> -->
         </configuration>
       </plugin>

sdk-platform-java/gax-java/gax-grpc/src/test/java/com/google/api/gax/grpc/GrpcLoggingInterceptorTest.java

@@ -32,7 +32,6 @@
 
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.mock;
-import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
@@ -83,7 +82,7 @@ void testInterceptor_basic() {
   void testInterceptor_responseListener() {
     when(channel.newCall(Mockito.<MethodDescriptor<String, Integer>>any(), any(CallOptions.class)))
         .thenReturn(call);
-    GrpcLoggingInterceptor interceptor = spy(new GrpcLoggingInterceptor());
+    GrpcLoggingInterceptor interceptor = new GrpcLoggingInterceptor();
     Channel intercepted = ClientInterceptors.intercept(channel, interceptor);
     @SuppressWarnings("unchecked")
     ClientCall.Listener<Integer> listener = mock(ClientCall.Listener.class);

sdk-platform-java/gax-java/gax-grpc/src/test/java/com/google/api/gax/grpc/InstantiatingGrpcChannelProviderTest.java

@@ -710,6 +710,7 @@ void testLogDirectPathMisconfigWrongCredential() throws Exception {
         InstantiatingGrpcChannelProvider.newBuilder()
             .setAttemptDirectPathXds()
             .setAttemptDirectPath(true)
+            .setEnvProvider(name -> null)
             .setHeaderProvider(
                 mock(HeaderProvider.class, Mockito.withSettings().withoutAnnotations()))
             .setExecutor(mock(Executor.class))