Fix adding new group members from admin area

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

CHANGELOG

@@ -17,7 +17,7 @@ v 7.11.0 (unreleased)
   - Add project activity atom feed.
   - Don't crash when an MR from a fork has a cross-reference comment from the target project on of its commits.
   - Include commit comments in MR from a forked project.
-  -
+  - Fix adding new group members from admin area
   - Add default project and snippet visibility settings to the admin web UI.
   - Fix bug where Slack service channel was not saved in admin template settings. (Stan Hu)
   - Move snippets UI to fluid layout

app/views/admin/groups/show.html.haml

@@ -60,7 +60,7 @@
 
         = form_tag members_update_admin_group_path(@group), id: "new_project_member", class: "bulk_import", method: :put  do
           %div
-            = users_select_tag(:user_ids, multiple: true, email_user: true)
+            = users_select_tag(:user_ids, multiple: true, email_user: true, scope: :all)
           %div.prepend-top-10
             = select_tag :access_level, options_for_select(GroupMember.access_level_roles), class: "project-access-select select2"
           %hr