Improve creating new users' group UX/UI

[pesarkhobeee]

I believe that we should be able to define a new group when we are creating a new user but unfortunately, that is impossible!
So from my point of view, this is a UX/UI problem which I hope somebody fixes that :)

[nextcloud-bot]

GitMate.io thinks possibly related issues are #434 (New sharing UI), #1309 (Improve backup codes UI/UX), #1963 (Improve user share suggestions), #9299 (Please improve user registration), and #4882 (Impersonating new LDAP user fails).

[skjnldsv]

Already fixed in #11193 😁