CI: Annotate errors for Github

[runephilosof-abtion]

As described on
https://docs.github.com/en/actions/writing-workflows/choosing-what-your-workflow-does/workflow-commands-for-github-actions

[runephilosof-abtion]

The annotations are not visible on "conversation" tab of a PR.

But they are visible on "Files changed"

[jeppester]

Looks like a fine little improvement.
To ensure that the rspec formatter works, could you make a commit that breaks rspec?

[runephilosof-abtion]

Made rspec fail in #2329
It annotates the rspec files with the errors, instead of the place where the error is raised, but I guess it is better than not annotating.

[runephilosof-abtion]

The gem maintainer is open to adding annotating the exception file/line
Drieam/rspec-github#75
https://github.com/Drieam/rspec-github/pull/76/files

[jeppester]

The gem maintainer is open to adding annotating the exception file/line
Drieam/rspec-github#75
https://github.com/Drieam/rspec-github/pull/76/files

Cool.

I don't like for this PR to stall while we are waiting, let's merge this for the value it gives us already.
Then we can upgrade if it becomes possible to show the exception location.