Context

#3620 (closed): add more jobs to parallelize tests more and thus reduce CI time.

Note that combining this MR with !6151 (merged) would reduce the time further. With the two MRs combined, I was able to get a pipeline that took 21 minutes to succeed: https://gitlab.com/tezos/tezos/-/pipelines/623968498

In addition to splitting jobs, this MR also:

!6139 (ef164a60) reduces count in a property-based test (PBT) of the protocol from 1000 to 300 because the test was simply too long for the CI. This was informally approved by @vch9 on Slack;
!6139 (8cd8ec43) have the build jobs, which are a bottleneck, not wait for sanity_ci. The cost is that we use more CI ressources when sanity_ci would fail, but since we now have manual pipelines, I think it is reasonable.

Manually testing the MR

Look at the CI.

Checklist

Document the interface of any function added or modified (see the coding guidelines)
Provide automatic testing (see the testing guide).
Select suitable reviewers using the Reviewers field below.
Select as Assignee the next person who should take action on that MR

Edited Aug 29, 2022 by Romain