Remove obsolete Maven artifacts from all of our repositories

[armiol]

At this moment, there are a lot of *-SNAPSHOT-* artifacts in our artifact repos. The vast majority of them are obsolete, and are no longer used.

In the scope of this issue, we need an automated solution for removing them.

For each artifact published, let's remove all the snapshots, except for the most recent 5.

Target repositories include:

• CloudRepo,
• Google Cloud Artifact Registry — non-viewable via HTTP,
• GitHub Packages in each of Spine Event Enging repositories.

Also, it is suggested to deal with the removal repo-by-repo, since each of them has its own API.

[armiol]

@MykytaPimonovTD for CloudRepo, there is this thing, which could help us deal with the issue.

[armiol]

@MykytaPimonovTD also, FYI. The similar thing for GCAR.

[armiol]

@MykytaPimonovTD lastly, here is the deal for GitHub Packages.