remove obsolete assertion

Author: igorbernstein2

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

@@ -150,13 +150,6 @@ public void testWithPoolSize() throws IOException {
 
  provider = provider.withPoolSize(2);
  provider.getTransportChannel().shutdownNow();
-
- try {
- provider.withPoolSize(3);
- fail("acceptsPoolSize() returned false; we shouldn't be able to set it again");
- } catch (IllegalStateException e) {
-
- }
  }
 
  @Test