Update selector it use JS-only class

app/assets/javascripts/protected_branches/ee/protected_branch_create.js

@@ -18,7 +18,7 @@
 
   gl.ProtectedBranchCreate = class {
     constructor() {
-      this.$wrap = this.$form = $('#new_protected_branch');
+      this.$wrap = this.$form = $('.js-new-protected-branch');
       this.buildDropdowns();
       this.$branchInput = this.$wrap.find('input[name="protected_branch[name]"]');
       this.bindEvents();

spec/support/protected_branch_helpers.rb

 module ProtectedBranchHelpers
-  def set_allowed_to(operation, option = 'Masters', form: '#new_protected_branch')
+  def set_allowed_to(operation, option = 'Masters', form: '.js-new-protected-branch')
     within form do
       find(".js-allowed-to-#{operation}").trigger('click')
       wait_for_requests