FIX: Correct error on add user modal (#23679)

spec/system/page_objects/pages/group.rb

@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+module PageObjects
+  module Pages
+    class Group < PageObjects::Pages::Base
+      def visit(group)
+        page.visit("/g/#{group.name}")
+        self
+      end
+
+      def find(selector)
+        page.find(".group #{selector}")
+      end
+
+      def add_users
+        find(".group-members-manage button.group-members-add").click
+        self
+      end
+
+      def select_user_and_add(user)
+        page.find(
+          ".modal-container .user-chooser .multi-select-header .select-kit-header-wrapper",
+        ).click
+        page.find(".modal-container .user-chooser .filter-input").set(user.username)
+        page.find(
+          ".modal-container li.email-group-user-chooser-row[data-value='#{user.username}']",
+        ).click
+        page.find(".modal-container button.add.btn-primary").click
+        self
+      end
+    end
+  end
+end