Add exclusion paths for coreclr CI builds

[safern]

cc: @ViktorHofer @jashook @trylek @jkoritzinsky

[trylek]

I have one non-blocking question but LGTM overall, thanks for fixing this!

[ViktorHofer]

We definitely need these changes in pr.yml as well.

[safern]

Updated to address feedback. Would appreciate another review.

[trylek]

Jarret is the expert on include / exclude precedence but to me this still looks good.

[jashook]

I think we probably should delete perf.yml.

[trylek]

@jashook - doesn't [didn't] "dotnet-coreclr perf" still use it?

[jashook]

Ya I think the pipeline will die with consolidation.

[trylek]

Looks like we might want to invite @DrewScoggins to this party...

[jashook]

Looks like the CI is still painfully slow to acquire machines.

[safern]

I will go ahead and merge this as builds were triggered just fine.

[DrewScoggins]

Thanks for the tag @trylek

Our current performance jobs only run on the internal side of AzDO, and as of now I do not see any of the new jobs there. Will we need to do additional work to bring that side of the house back online?

[trylek]

@DrewScoggins - For the various side CoreCLR pipelines like gcstress, jitstress, r2r et al. I have already created their counterparts for the runtime repo. For dotnet-coreclr perf I don't have the credentials to create an internal pipeline. I can either create that as a public pipeline (if that's desirable) or you or someone with the access rights needs to do it or grant me rights to do that :-).

[jashook]

@DrewScoggins @trylek @BruceForstall I believe porting the existing pipeline as is, is most likely the incorrect way to move forward. We should meet to discuss what things look like going forward before making this port.