Merge pull request #6299 from jtattermusch/fix_5912

Fix Grpc.IntegrationTesting.InteropClientServerTest flake 

src/csharp/Grpc.IntegrationTesting/InteropClient.cs

@@ -494,7 +494,8 @@ namespace Grpc.IntegrationTesting
                 }
 
                 var ex = Assert.ThrowsAsync<RpcException>(async () => await call.ResponseStream.MoveNext());
-                Assert.AreEqual(StatusCode.DeadlineExceeded, ex.Status.StatusCode);
+                // We can't guarantee the status code always DeadlineExceeded. See issue #2685.
+                Assert.Contains(ex.Status.StatusCode, new[] { StatusCode.DeadlineExceeded, StatusCode.Internal });
             }
             Console.WriteLine("Passed!");
         }