bug #4685 Improve Symfony 5 compatibility (keradus)
bug #4685 Improve Symfony 5 compatibility (keradus)

This PR was merged into the 2.15 branch.

Discussion
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Improve Symfony 5 compatibility

Closes #4684

one can install contract on his own, even if he is using Sf version that does not rely on contracts,
for that, we need to check if actually Sf component relies on contract, not only the fact that contract exists.

TODO:
- [x] look for other places when we check that contract exists and nothing more (edit by @julienfalque: only found one in the related test, not sure it's worth the hassle)

Commits
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03f6fd5bf Better Sf5 compatibility

FriendsOfPHP/PHP-CS-Fixer,gharlan/PHP-CS-Fixer,GrahamCampbell/PHP-CS-Fixer,keradus/PHP-CS-Fixer,keradus/PHP-CS-Fixer,Slamdunk/PHP-CS-Fixer,Slamdunk/PHP-CS-Fixer,kubawerlos/PHP-CS-Fixer,GrahamCampbell/PHP-CS-Fixer,FriendsOfPHP/PHP-CS-Fixer,gharlan/PHP-CS-Fixer,kubawerlos/PHP-CS-Fixer,SpacePossum/PHP-CS-Fixer,SpacePossum/PHP-CS-Fixer