chore: Use currentUser from authentication

packages/backend/src/helpers/authentication.ts

@@ -1,10 +1,6 @@
 import { Request, Response, NextFunction } from 'express';
 import User from '../models/user';
-import UserType from '../types/user';
-
-interface RequestWithCurrentUser extends Request {
-  currentUser: UserType
-}
+import RequestWithCurrentUser from '../types/express/request-with-current-user';
 
 const authentication = async (req: RequestWithCurrentUser, _res: Response, next: NextFunction) => {
   // We set authentication to use the sample user we created temporarily.