Drop Admin attribute based on LDAP when login (continue #1743) (#8849)

Drop Admin attribute based on LDAP when login (continue #1743) (#8849)

* Update User information in Gitea based on LDAP when login

* Update Admin Flag only if exist in settings

* Fix affectation

* Update models/login_source.go

Co-Authored-By: JustKiddingCode <JustKiddingCode@users.noreply.github.com>
* Better ident

* Apply suggestions from code review

Update user information

Co-Authored-By: 6543 <24977596+6543@users.noreply.github.com>
* Make fmt

* add err handling

* if user exist but login is Prohibit return return nil, and Prohibit err

* keep login speed

* User sync is implemented at #1478 - so only make sure that admin acces is drpoed if changed

* handle error and still use async task

* no async

* only update admin if Sync is enabled

* update two comments

* add lafriks suggestions

Co-Authored-By: Lauris BH <lauris@nix.lv>
* if adminFilter is set - use it

Co-Authored-By: Lauris BH <lauris@nix.lv>
* Update models/login_source.go

well - I should look more detaild at suggestions :D

Co-Authored-By: Lauris BH <lauris@nix.lv>
* make it work again

* set is_admin value to user

* look nicer