`minProperties` and `maxProperties` are only applicable on objects.

https://www.learnjsonschema.com/draft4/validation/minproperties/ 

https://json-schema.org/draft-04/draft-fge-json-schema-validation-00#rfc.section.5.4.2

… be RFC 3986 compliant (#800)

This pull request introduces new validators for URI and relative
references and integrates them into the `FormatConstraint` class. The
changes also include corresponding unit tests to ensure the validators
work as expected.

### New Validators:
*
[`src/JsonSchema/Tool/Validator/UriValidator.php`](diffhunk://#diff-2019f410f3ef4cdf8478ffa71444226beb8a118d60b3337c40eaaec8d3aef7a3R1-R65):
Added a new class `UriValidator` to validate URIs according to RFC 3986
and RFC 5322 for `mailto:` URIs.
*
[`src/JsonSchema/Tool/Validator/RelativeReferenceValidator.php`](diffhunk://#diff-0bfeeb9c38593a2d65cc2e8c49fe873c78765eac81c00cf0a398bd754ca9c7a8R1-R53):
Added a new class `RelativeReferenceValidator` to validate relative
references according to RFC 3986.

### Integration into `FormatConstraint`:
*
[`src/JsonSchema/Constraints/FormatConstraint.php`](diffhunk://#diff-44020f0c0690a2a4c1c446e97185986c31b19374b4a99f4b0970c5df36279067L104-R114):
Integrated the new `UriValidator` and `RelativeReferenceValidator` into
the `check` method to replace the previous inline validation logic for
`uri` and `uri-reference` formats.

### Unit Tests:
*
[`tests/Tool/Validator/UriValidatorTest.php`](diffhunk://#diff-6b107cb8679795fb59c070ba500d0646f6d357e4c03a585f4a0c67181e4101fcR1-R49):
Added unit tests for `UriValidator` to ensure it correctly validates
valid and invalid URIs.
*
[`tests/Tool/Validator/RelativeReferenceValidatorTest.php`](diffhunk://#diff-97a7acc2a16f7653d307a16e356c7545b0a0bc26156ce60f7ca13332a6656729R1-R40):
Added unit tests for `RelativeReferenceValidator` to ensure it correctly
validates valid and invalid relative references.

# Closing keywords
fixes #685

After considering the options and rethinking the problem we are trying
to solve I came top the conclusion we don't need a external library
which can handle PHP class equality. Since we are working with JSON we
only have scalar types (boolean, float, integer and string) and two
collections types array and `stdClass`.
This made it simple to write our own deep comparison.

Fixes #753