[experiment] Run Unit tests with paratest

The disconnect between paratest and run-tests.sh timings looked a bit too much, so I checked phpunit test timings in HEAD and found bugs in the run-tests.sh logic (recently introduced by me).

📌 Try a shorter polling time in run-tests.sh Active is the issue.

https://git.drupalcode.org/project/drupal/-/jobs/2938499 reports 42 seconds to run tests now so a better baseline for comparison.

Also, in the past when I've used paratest on projects I've had problems with deprecation testing and how Symfony adds the info. Maybe with the recent PHPUnit / Symfony PHPUnit Bridge changes this is no longer a problem but we need to confirm whether deprecation fails are still reported correctly - both that the test fails and that we can see the deprecation that causes the fail.

plain PHPUnit: 1 min 54 secs
paratest: 24 secs
run-tests: 31 secs

MR!11573 combines 🌱 [meta] Support PHPUnit 11 in Drupal 10 Postponed with 📌 [PP-1][CI] Spin off Drupal Components tests in a job of their own Postponed and runs Drupal\Component tests using paratest without any change.

PHPUnit CLI: PHP 8.3 43sec; PHP 8.4 43sec; PHP 8.5 44sec.

paratest (using 72 processes): PHP 8.3 18sec; PHP 8.4 19sec; PHP 8.5 23sec.

Adding a test failure and a deprecation, observations:

• --testdox command line toggle does not seem to work
• deprecation reporting seem to be working fine (re comment #5 above)

The missing testdox output is caused by a change in PHPUnit 11.5.12 that is not matched by paratest 7.8.3

With some hacking I managed to fix it here, but will require being fixed upstream.

#11 is actually fixed upstream already in 7.9.0, that is only compatible with PHPUnit 12 - this will be the bigger problem to use paratest in Drupal: it only supports the latest PHPUnit version, that Drupal is consistently late in adopting at the moment.