ID does not necessarly have be absolute 

This line:
https://github.com/danubetech/verifiable-credentials-java/blob/main/src/main/java/com/danubetech/verifiablecredentials/validation/Validation.java#L16

When validating an VC's ID I don't think it necessarily has to be 'absolute' ie a fully resolvable url.

It can just be a UUID to preserve privacy.

Any way to make this optional or add validation options to bypass this check?