Feature request: provide a way to produce a sarif file whose content does not include issues from a baseline

[jraygauthier]

At first, I would have assumed that $ sarif diff might do just that. However it instead produce a differential json report.

If we had this capability to produce such "new issues from baseline" sarif file, it would then be possible to reuse the other commands on this new sarif.

I had a look at filters (--filter) and those do not appear to offer this capability either (e.g.: create a filter from the path to a baseline).