Bump minimum deps compatibility

[amenophis]

This PR remove compatibility with php < 8.1 and symfony < 5.4.
It also add compatibility with symfony 7.0

[amenophis]

@dunglas Don't know why i have to add the dependency on symfony/validator, any idea ?

The error was:
PHP Fatal error: During class fetch: Uncaught ReflectionException: Class "Symfony\Component\Validator\Mapping\Loader\AutoMappingTrait" not found while loading "Symfony\Bridge\Doctrine\Validator\DoctrineLoader". in /home/jeremy/dev/github.com/amenophis/dunglas-doctrine-json-odm/vendor/symfony/error-handler/DebugClassLoader.php:337

[dunglas]

That's likely a bug (a missing class_exists() in Symfony).

[amenophis]

ok, @dunglas do you think it can be merged in state (and released), or should we fix the symfony bug before ?

[back-2-95]

Is there some Symfony issue which this is waiting?

[dunglas]

Thank you @amenophis!!