beforeUnload prompt tests

[Osseta]

This PR adds tests to demonstate that handling browser beforeUnload prompts stopped working in Chrome 137 and later.

The test runs on chrome 135,136,138,139.

versions 135 & 136 pass
versions 138 & 139 fail.

$ bundle install
$ bundle exec rake spec_multi_chrome

Failures:

  1) testing with chrome_139 should accept browser modal
     Failure/Error: raise Capybara::ModalNotFound, "Unable to find modal dialog#{" with #{text}" if text}"

  2) testing with chrome_138 should accept browser modal
     Failure/Error: raise Capybara::ModalNotFound, "Unable to find modal dialog#{" with #{text}" if text}"

Finished in 10.22 seconds (files took 0.59535 seconds to load)
4 examples, 2 failures

Failed examples:

rspec './spec/selenium_spec_multi_chrome.rb[1:4]' # testing with chrome_139 should accept browser modal
rspec './spec/selenium_spec_multi_chrome.rb[1:3]' # testing with chrome_138 should accept browser modal

The test is simple:

    session.visit('/with_unload_alert')
    session.fill_in 'data', with: 'this is data'
    session.accept_confirm do
      session.click_link('Go away')
    end
    expect(session).to have_text('Hello world')

In chrome 137 and later the modal is never shown and instead the link is followed without prompting.

[Osseta]

There is a bug in selenium-webdriver as discussed on this issue. #2824