better precommit by showing YAML behavior pre-fix

Author: evelez7

clang-tools-extra/test/clang-doc/conversion_function.cpp

@@ -12,6 +12,7 @@ struct MyStruct {
 };
 
 // Output incorrect conversion names.
+// CHECK-YAML:         Name:            'operator type-parameter-0-0'
 // CHECK-YAML-NOT:     Name:            'operator T'
 
 // CHECK-HTML-NOT: <h3 id='{{[0-9A-F]*}}'>operator T</h3>