Make this test harder to pass

test/core/end2end/tests/simple_request.c

@@ -203,6 +203,9 @@ static void test_invoke_10_simple_requests(grpc_end2end_test_config config) {
 }
 
 void grpc_end2end_tests(grpc_end2end_test_config config) {
-  test_invoke_simple_request(config);
+  int i;
+  for (i = 0; i < 10; i++) {
+    test_invoke_simple_request(config);
+  }
   test_invoke_10_simple_requests(config);
 }