Support Symfony 7 (#1284)

Add tests for symfony 6 (#1281)

* Test symfony 6

* Use command constant if available

Fix form help overriding (#1273)

Merge branch 3.3

Add versions dependencies details in README (#1260)

* Add versions in README

* Remove BRANCHES.md

CS Fixer (#1243)

* CS Fixer

Fix renderer tests (#1228)

Fix renderer tests and make sure Symfony 4 working properly.

Update deprecated sameas twig test (#1215)

Replace 'horizontal' option with 'layout' (#1044)

Allow twig2 (#1205)

I _think_ this will allow Twig2, but am not sure if it should be ^2.0 or ~2.0 (or something else)