Disable builds for 3.10.0a4, and enable a nightly 3.10-dev build

[YannickJadoul]

Description

Temporary fix for #2774. Meanwhile, this also adds 3.10-dev nightly builds from deadsnakes.

[YannickJadoul]

@henryiii, this seems to be working. But I'm not sure the nightly Python versions are really worth the extra complexity (and additional almost-never-executed "Setup Python X.Y (nightly)" step). Maybe it should be a separate matrix of jobs, where we also test some debug versions? I don't know.

At any rate, feel free to push to this branch to propose changes :-)

[YannickJadoul]

@henryiii, this seems to be working.

Neeeeeeeeevermind that. Why can't it find the correct Python? :-(

[henryiii]

I'd add a new job at least, I think. Or maybe not, this is not that inelegant. A dev only set might be not unreasonable.

[YannickJadoul]

Heh...

Run deadsnakes/[email protected]
  with:
    python-version: 3.10-dev
    debug: false

And yet 10-dev is still acting as if debug was specified. I might need to fix my own PR deadsnakes/action#18

[YannickJadoul]

Submitted a fix: deadsnakes/action#20

@henryiii, if you want to merge this before deadsnakes/action#20 would be merged, that's possible. Either as-is (with my branch, temporarily), or without the last commit (which will install the 3.10-dev debug version, but eh, should be fine).

[YannickJadoul]

@henryiii, if you want to merge this before deadsnakes/action#20 would be merged, that's possible. Either as-is (with my branch, temporarily), or without the last commit (which will install the 3.10-dev debug version, but eh, should be fine).

That went fast. Scratch that, the PR already got merged, and a new release released :-)

Python 2.7 doesn't work with deadsnakes/action (because there's no python2.7-venv package, and no venv), but ... well let's cross that bridge (and make that PR) when we need to?