Add ability to test on Firefox using selenium

Problem/Motivation

Once #3421202: Enable W3C-compliant webdriver testing lands we will be able to test using selenium/standalone-firefox.

Steps to reproduce

Add

.with-selenium-firefox: &with-selenium-firefox
  name: selenium/standalone-firefox:127.0
  alias: selenium
  variables:
    JAVA_OPTS: "-Dwebdriver.firefox.logfile=/builds/geckodriver.log"
    SE_NODE_OVERRIDE_MAX_SESSIONS: "true"
    SE_NODE_MAX_SESSIONS: "5"
    SE_START_XVFB: "false"
    SE_START_VNC: "false"'🖱️️️ PHPUnit Functional Javascript (selenium firefox)':
  <<: [ *with-composer, *run-tests, *default-job-settings ]
  when: manual
  parallel: 4
  variables:
    TESTSUITE: PHPUnit-FunctionalJavascript
    CONCURRENCY: 15
    KUBERNETES_CPU_REQUEST: "24"
    MINK_DRIVER_ARGS_WEBDRIVER: $MINK_DRIVER_ARGS_WEBDRIVER_FIREFOX_W3C
  services:
    - <<: *with-database
    - <<: *with-selenium-firefox
  after_script:
    - echo $MINK_DRIVER_ARGS_WEBDRIVER
    - sed -i "s#$CI_PROJECT_DIR/##" ./sites/default/files/simpletest/phpunit-*.xml || true
    - cp /builds/geckodriver.log ./

To gitlab pipeline.

Proposed resolution

• Fix webdriver and update version to one that supports firefox testing. Firefox and chrome weddriver implement is different. Firefox does not scroll into view when a clicking on an element, Chrome does. This is due to https://stackoverflow.com/questions/44777053/selenium-movetargetoutofbou.... The webdriver-classic-driver does https://github.com/minkphp/webdriver-classic-driver/blob/73ad0b6ce21cf69...
• Fix tests - for example performance tests are tied to chrome

Remaining tasks

User interface changes

None

API changes

TBD - hopefully none

Data model changes

None

Release notes snippet

TBD