chore: test Symfony 5.3 + improve SYMFONY_DEPRECATIONS_HELPER

[vincentchalamon]

Q	A
Bug fix?	no
New feature?	no
BC breaks?	no
Deprecations?	no
Tests pass?	yes
Fixed tickets	N/A
License	MIT

[codecov]

Codecov Report

Merging #112 (156ad75) into main (3c75b6d) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##               main     #112   +/-   ##
=========================================
  Coverage     76.96%   76.96%           
  Complexity      220      220           
=========================================
  Files            36       36           
  Lines          1033     1033           
=========================================
  Hits            795      795           
  Misses          238      238           

Flag	Coverage Δ
phpunit	76.96% <ø> (ø)

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