SARIF output support

[marksteele]

Would be awesome to be able to specify a folder, and have the validator validate all yaml files in the folder and output a SARIF output file.

Then this could be integrated into the Github scan results and annotate PRs directly with results (via the upload sarif action)

https://docs.github.com/en/code-security/code-scanning/integrating-with-code-scanning/sarif-support-for-code-scanning

[mpalmer]

I'd gladly accept a quality PR to implement such support.