Use specific Jenkins nodes for releases

[yrodiere]

This should be safer.

It requires moving the snapshot publishing to a dedicated job, but ORM already does that, so we might as well align.

I took this opportunity to clean up sections about CI in CONTRIBUTING.md/MAINTAINERS.md.

We'll need to backport this to all branches where we want to perform releases or publish snapshots...

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[marko-bekhta]

Thanks! This looks like a nice improvement 🎉

[yrodiere]

We'll need to backport this to all branches where we want to perform releases or publish snapshots...

Discussed elsewhere, but here's the conclusion. We (or rather @marko-bekhta 😬) will backport:

• the removal of snapshot publishing in the main Jenkinsfile to all branches
• the whole patch (except maybe changes to .md files) to still-maintained branches

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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