spec/features/users/signup_spec.rb failed on master

Job #238602254 failed for 2ba7f6f6:

Failures:

  1) Signup username validation shows a pending message if the username availability is being fetched
     Failure/Error: expect(find('.username > .validation-pending')).not_to have_css '.hide'

     Capybara::ElementNotFound:
       Unable to find visible css ".username > .validation-pending"