Use BrowserKit with Guzzle client

[claudiu-cristea]

This PR is built on top of #620.

Problem

• Drop Goutte Driver. Support D10, Drush 11, Symfony 6 #620 allows to get rid of Goutte driver and use directly BrowserKit driver
• However, with BrowserKit, which uses the HttpBrowser, the forms that are posting files are failing. The reason is this [Mime] Form field values with integer keys not resolved correctly  symfony/symfony#47504 (at least I couldn't make it work)
• This issue could not be reproduced by Drupal Test Traits because they are using BrowserKit with Guzzle as client, via Drupal\Tests\DrupalTestBrowser, see https://gitlab.com/weitzman/drupal-test-traits/-/blob/2.x/src/BrowserKitTrait.php#L21

Proving the bug

I've created a "test only" PR #623. See the failures here https://github.com/claudiu-cristea/drupalextension/actions/runs/3411428842

Proposal

Use Drupal\Tests\DrupalTestBrowser as BrowserKitDriver client. This also has the advantage that is aligned with Drupal core PHPUnit tests.

Here's a diff to #620 https://github.com/claudiu-cristea/drupalextension/pull/1

[claudiu-cristea]

Tests:

• Without this PR (fail) https://github.com/claudiu-cristea/drupalextension/actions/runs/3411442593/jobs/5675645228
• With this fix (pass) https://github.com/claudiu-cristea/drupalextension/actions/runs/3411442593