Update project member controller to match recent master logic

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

app/controllers/projects/project_members_controller.rb

@@ -25,18 +25,16 @@ class Projects::ProjectMembersController < Projects::ApplicationController
   end
 
   def create
-    if params[:user_ids].blank? && params[:group_ids].blank?
+    if params[:user_ids].blank?
       return redirect_to(namespace_project_project_members_path(@project.namespace, @project), alert: 'No users or groups specified.')
     end
 
-    if params[:user_ids].present?
     @project.team.add_users(
       params[:user_ids].split(','),
       params[:access_level],
       expires_at: params[:expires_at],
       current_user: current_user
     )
-    end
 
     redirect_to namespace_project_project_members_path(@project.namespace, @project), notice: 'Users were successfully added.'
   end