feat: add user submission functionality

src/modules/submissions/decorators/submission-answer.decorator.ts

@@ -0,0 +1,6 @@
+import { Validate } from 'class-validator';
+import { SubmissionAnswerValidator } from '../validators/submission-answer.validator';
+
+export const SubmissionAnswer = () => {
+  return Validate(SubmissionAnswerValidator);
+};