In case a resource method was in the same class as another method by the same name, but different method parameters, a ClassCastException was thrown. This was because the identifier for the rest invoker was the same. MethodParameter.toString does not return the List<String> wrapper, only the type for the param container, i.e. String. Also, small cleanup for the HashUtil, no need for the additional substring call.

• Closes: #40831