Exclude entity types from purge (compatibility with Structure Sync)

I created a patch of my current changes, also committed to the issue fork. The patch is only for replicable builds.

I created an alternative solution, adding only and exclude lists to the purge method to give even more control. Here is a static patch for reproducible builds.

No that this project has a .gitlab-ci.yml for pipeline testing I am going to trigger a pipeline. This is in relation to testing, see 🐛 "Directory not empty" warning triggered by something in CI Active