[HOLD end of August] Deal with loss of free continuous Cirrus CI

[IAlibay]

Fixes #4216

Changes made in this Pull Request:

• Drop running Cirrus CI on PRs, now will only run on a twice weekly cron
• Add badge so we know if things are breaking

Developers certificate of origin

• I certify that this contribution is covered by the LGPLv2.1+ license as defined in our LICENSE and adheres to the Developer Certificate of Origin.

---

📚 Documentation preview 📚: https://mdanalysis--4234.org.readthedocs.build/en/4234/

[github-actions]

Linter Bot Results:

Hi @IAlibay! Thanks for making this PR. We linted your code and found the following:

There are currently no issues detected! 🎉

[codecov]

Codecov Report

Patch and project coverage have no change.

Comparison is base (6e80c28) 93.62% compared to head (8b91638) 93.62%.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #4234   +/-   ##
========================================
  Coverage    93.62%   93.62%           
========================================
  Files          193      193           
  Lines        25304    25304           
  Branches      4064     4064           
========================================
  Hits         23692    23692           
  Misses        1096     1096           
  Partials       516      516           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[RMeli]

LGTM, thanks for all the CI/CD work @IAlibay!

[RMeli]

Suggested change

	print(env.get("CIRRUS_PR") != None)
	print(env.get("CIRRUS_BASE_BRANCH") == "develop")
	print(env.get("CIRRUS_PR") == None)
	print(env.get("CIRRUS_BRANCH") == "develop")

Maybe worth changing this debug print?

[orbeckst]

Thanks. Presumably, the cron job won't run out of free minutes?

From what it sounded in discussions elsewhere, there's not much we can do about this right now apart from paying for these runners.

[IAlibay]

Thanks. Presumably, the cron job won't run out of free minutes?

From what it sounded in discussions elsewhere, there's not much we can do about this right now apart from paying for these runners.

I did a back of the envelope calculation in #4216 - we should be fine but we'll need to check exactly how many tokens are used up in a release.