Experiment workflow pipeline filtering

[PVince81]

Part of https://github.com/nextcloud/server/issues/33468

This should accelerate some of the JS-only changes and lib updates.

[PVince81]

seems it won't be that easy: https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#example-including-paths

the docs state that excluding runs that are "expected" to pass will prevent merging