We've got flaky specs

[Judahmeek]

https://app.circleci.com/pipelines/github/shakacode/react_on_rails_pro/2431/workflows/4efd228d-c93e-46fc-91d1-4296597d98c3/jobs/23309

https://app.circleci.com/pipelines/github/shakacode/react_on_rails_pro/2398/workflows/88a75908-e1d8-4a3d-b819-e3fb413a9db1/jobs/23022

Both of these specs passed on second attempt.

[Judahmeek]

@AbanoubGhadban Sergey suggested https://github.com/makandra/capybara-lockstep, but I'm not sure that package can help with streaming specs. Sergey's other suggestion was that we modify HiChee's helper methods as necessary:

    def wait_for_ajax
      find('body[data-are_ajax_requests_pending="false"]')
      reset_wait_for_ajax
    end

    def reset_wait_for_ajax
      execute_script <<~JAVASCRIPT
        if (document.body.getAttribute('data-are_ajax_requests_pending') === "false") {
          document.body.removeAttribute('data-are_ajax_requests_pending')
        }
      JAVASCRIPT
    end

    def ajax_log_raw
      evaluate_script <<~JAVASCRIPT
        document.body.getAttribute('data-ajax_requests_log')
      JAVASCRIPT
    end

    def ajax_log
      raw_log = ajax_log_raw
      return [] if raw_log.blank?

      ended_requests = raw_log.scan(/(\d+)\tended\t([^\n]+)/).each_with_object({}) do |attrs, result|
        result[attrs[0]] = attrs[1].to_i
      end

      raw_log.scan(/(\d+)\tstarted\t([^\t]+)\t([^\n]+)/).map do |attrs|
        AJAX_LOG_FIELDS.zip(attrs << ended_requests[attrs[0]]).to_h
      end
    end

    def ajax_log_matching(url_regex, status:)
      ajax_log.select { |entry| entry[:url].match?(url_regex) && entry[:status] == status }
    end

    def wait_for_ajax_log_matching(url_regex, status:, qty: 1, timeout: 20)
      (timeout / TIMEOUT_BETWEEN_LOOPS_SEC).to_i.times do
        return if ajax_log_matching(url_regex, status:).size >= qty

        sleep(TIMEOUT_BETWEEN_LOOPS_SEC)
      end
      raise "wait_for_ajax_log_matching: timeout expired\n\n#{ajax_log_raw}"
    end

    def waiting_for_ajax(url_regex, status:)
      n_requests = ajax_log_matching(url_regex, status:).size
      yield
      wait_for_ajax_log_matching(url_regex, status:, qty: n_requests + 1)
    end

[Judahmeek]

I've also created #544, which should enable us to quickly rerun only the failing specs.

Edit: I had both previously identified flaky specs fail in CI while trying to merge this PR! 😂

Flaky specs:
React Router Sixth Page behaves like streamed component tests doesn't hydrate status component if packs are not loaded fails repeatedly. Needs a serious fix.
Pages/async_on_server_sync_on_client progressively renders the page content