Hello!

This PR aims to add support for list type in the Typeconstraint.

This is done by using the new PHP 8.1 function array_is_list, after checking that the value is an array with is_array function.

Here is an example of use:

#[Assert\Type('list')]
private $value;

I consider doing an other PR to add associative_array type aswell. Or if you think it's ok, I can also add it in an other commit on this one.

--- UPDATE

After fabpot comment, I added an other commit to support associative_array type aswell :

#[Assert\Type('associative_array')]
private $value;

An associative_array is an array that is not a list. Moreover, this means that an empty array will not be considered as an associative_array.

Best regards