#11965 fix cfreactor on Python 3.8 and Python 3.9

[graingert]

Scope and purpose

Fixes #11965

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[graingert]

@adiroiban what do you want to do re the automated tests on this one? the macos tests are only run on 3.11 maybe they should run on 3.8 also?

[adiroiban]

Thanks. Enabling them on 3.8 should be ok.

I see that we also run Windows tests on 3.8 and 3.11.
Maybe also update Windows to run on 3.8 and 3.12

so for macOS and Windows we can run on the oldest and newest version that we support.

Do you use Twisted with cfreactor ? If yes, then I think we should run the cfreator tests on any Python version that you use.

[adiroiban]

Thanks. Looks good.

Please also consider enabling the GHA macOS tests for python 3.8.

With that, this should be ready to land.

thanks again!

[graingert]

Do you use Twisted with cfreactor ? If yes, then I think we should run the cfreator tests on any Python version that you use.

I do not, I only noticed this by running mypy with 3.8.0

[graingert]

I'll enable macos 3.8 tests in a followup