[DX] include actual count in collection constraint errors

[dkarlovi]

Really small life quality tweak.

Currently, I'm getting this:

      JSON does not validate. Violations:
        - [] There must be a minimum of 30 items in the array

I'd like this:

      JSON does not validate. Violations:
        - [] There must be a minimum of 30 items in the array, 10 found

[shmax]

SGTM. Please open a PR.

[DannyvdSluijs]

As a starter error messages are defined in the \JsonSchema\Exception\InvalidArgumentException\ConstraintError class. For this report you would need to alter the message and where it is being used such as in the \JsonSchema\Constraints\CollectionConstraint, see here, where you'll need to pass the number of items found.

The same improvement should be suggested for the max items as well.