chore(ci) some tweaks to burn less cpu cycles

[Tieske]

No description provided.

[Tieske]

seems to fail on this again: actions/checkout#23

[curiositycasualty]

So this burns less CPU.. more intelligently managing the cancellation of related builds when one of them fails?
if it works.

[Tieske]

@curiositycasualty yes, some hints by @wheelerlaw ;

• better cancellation, so pushing twice in a row to the same branch/PR will cancel the first job
• running on pull_requests, and "on push" only if to master to prevent the typical dual jobs, though this works mostly for shortlived branches.

In this case, the push and pull_request are in different workflows because on the PR I needed to disable one test, see 2nd commit and the internal slack discussion https://kongstrong.slack.com/archives/C027PKSNBC5/p1666268700904629?thread_ts=1666258977.473739&cid=C027PKSNBC5