DX: do not enforce time limits for tests

[kubawerlos]

Since:

PHP extension pcntl is required for enforcing time limits

and playing with time limits is not helpig much, let's try to not use pcntl .

[keradus]

and playing with time limits is not helpig much, let's try to not use pcntl .

we Drop speedtrap PHPUnit listener not because we have issues with weird slowness of tests reported, but because the feature got incorporated into PHPUnit itself and we no longer need dedicated listener for it

Also, i believe we simply misconfigured the feature - #5435

[coveralls]

Coverage remained the same at 91.971% when pulling 94498b2 on kubawerlos:do-not-install-pcntl-extension-on-ci into 21934b5 on FriendsOfPHP:2.17.

[keradus]

green: #5435