Cut middle version from CI

[max-sixty]

Testing for 3.10 seems fairly low value — is there a realistic case where 3.10 would fail but 3.9 & 3.11 would pass?

Merging this would cut the CI queue...

[kmuehlbauer]

Might only help if different versions of dependencies are pulled in. But that might be such a rare case the user issues should be enough to handle.

We would need to remove the status checks from the required tests in the repo Settings-Branches.

[kmuehlbauer]

I've removed those builds from required tests in the repo Settings-Branches.

[max-sixty]

FYI one thing we do in PRQL is have a limited set of tests on PRs which cover 98% of cases with about 30% of the runtime — and then the full set of tests after merge. (And an even fuller set every night)

So we could do that sort of thing here if we wanted to ensure we see very rare issues before a user does without slowing down PRs.

(Not sure whether CI queues are a problem though, not worth spending time on it they're not)