align validator datamodels

[cmungall]

convergent evolution between:

https://github.com/deepakunni3/linkml-validator/blob/main/linkml_validator/models.py

https://github.com/linkml/linkml-model/blob/main/linkml_model/model/schema/validation.yaml
(hmm, looks like there is no python expression of this yet)

the linkml-model one is itself based on the SHACL validation datamodel, and has URIs back to it

[deepakunni3]

Omg! This is so cool! I didn't even realize there was a validation schema in linkml :D