fix(validation): ValidationException causes TypeError exception when called with $code=null

[KernelMrex]

Q	A
Branch?	3.3
Tickets
License	MIT
Doc PR

After update to 3.3.3, ValidationException called in custom validators code may cause issued.

For example: If you previously used ValidationException with only 1st string argument, after migration to 3.3.3 backward backward compatibility is broken.

Failed asserting that exception of type "TypeError" matches expected exception
"ApiPlatform\Validator\Exception\ValidationException". Message was: "Exception::__construct(): Argument #2 ($code) must be of type int, null given" at
/app/vendor/api-platform/core/src/Validator/Exception/ValidationException.php:84

[KernelMrex]

May I should add some tests to cover ValidationException constructor?

[soyuka]

Nice thanks!