Allow to ignore non OpenApi attributes

[DerManoMann]

Adds an option to AttributeAnnotationFactory to ignore non OpenApi annotations and not instantiate them.

This can be done by either instantiating the AttributeAnnotationFactory yourself or by configuring this in the Generator.

(new Generator())
    ->setConfig([
        'generator' => [
            'ignoreOtherAttributes' => true,
        ],
    ]);

Fixes #1747