remove unneeded Relation#all from Group#user_removed

git-svn-id: http://svn.redmine.org/redmine/trunk@12536 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/models/group.rb

@@ -68,7 +68,6 @@ class Group < Principal
       MemberRole.
         includes(:member).
         where("#{Member.table_name}.user_id = ? AND #{MemberRole.table_name}.inherited_from IN (?)", user.id, member.member_role_ids).
-        all.
         each(&:destroy)
     end
   end