Sarif merging

[nojaf]

Is your feature request related to a problem? Please describe.

GitHub Actions no longer accepts multiple sarif files for upload.
This is biting my in every project where I use analyzers.

Describe the solution you'd like
Can we add a MSBuild target that accepts an array/list of projects and invokes the cli in one go?

<Target Name="AnalyzeFSharpProjects" DependsOnTargets="_AnalyzeFSharpProject" />

Describe alternatives you've considered
It is possible to merge these sarif files, see https://github.com/fsprojects/fantomas/blob/1a6f2dbff5bf25b4fd9fbd6315a8b8cf8bb005f8/sarif.fsx#L231

But that requires everyone to deal with this themselves.
So maybe a breaking change in the MSBuild targets is the simpler thing.

Additional context
I don't have the right answer here, happy to discuss.

[TheAngryByrd]

Just looking around, I see things like:

• github merge-results - Merges multiple SARIF files into a single SARIF file.
• the copy command from sarif tools seems to be able to merge

I wonder if these would be sufficient (haven't tried).

[nojaf]

Thanks, I'll try those and maybe just document what worked well over here!