(core) do not allow anonymous user to set a name

Summary:
Only allow authorized users to set names. This excludes the anonymous user.

Seems to be a narrow issue isolated to the `POST /api/profile/user/name` endpoint, other `profile` posts/deletes are already restricted to authorized users.

Test Plan: added a test

Reviewers: dsagal

Reviewed By: dsagal

Differential Revision: https://phab.getgrist.com/D2574

app/gen-server/ApiServer.ts

@@ -320,7 +320,7 @@ export class ApiServer {
     // Body params: string
     // Update users profile.
     this._app.post('/api/profile/user/name', expressWrap(async (req, res) => {
-      const userId = getUserId(req);
+      const userId = getAuthorizedUserId(req);
       if (!(req.body && req.body.name)) {
         throw new ApiError('Name expected in the body', 400);
       }