Localization test is flaky (maybe mainly in CI)

[jagthedrummer]

In one of my projects I often get errors in test/controllers/application/localization_test.rb.

I notice it most often in GitHub Actions.

The errors look like this:

ApplicationControllerTest
  test_team_locale_is_nil,_user_locale_is_nil                    ERROR (0.42s)
Minitest::UnexpectedError:         ActionController::UrlGenerationError: No route matches {:action=>"any_action", :controller=>"application"}
            test/controllers/application/localization_test.rb:35:in `block in <class:ApplicationControllerTest>'

  test_user_not_signed_in_and_browser_sends_HTTP_ACCEPT_LANGUAGE_with_unknown_valueERROR (0.11s)
Minitest::UnexpectedError:         ActionController::UrlGenerationError: No route matches {:action=>"any_action", :controller=>"application"}
            test/controllers/application/localization_test.rb:96:in `block in <class:ApplicationControllerTest>'

When it happens there are always 9 errors coming from that test file. Often it's the only failure. Just re-running the tests usually doesn't help, but pushing an empty commit does. This may to indicate some sort of ordering problem.