[ci] Decrease build times

[ofek]

(Opening this while it's in my mind)

While overall build times are faster than before, individual jobs take a bit longer than on AppVeyor

From

pywin32/setup.py

Lines 22 to 24 in 5f47dc1

	At a minimum, you must have the same version of Microsoft Visual C++ that is
	used for the Python version you are building, plus the Windows 8.1 SDK. Note
	that the Windows 8.1 SDK is often bundled with Microsoft Visual C++.

Windows 8.1 SDK is a hard dependency

It didn't seem available on GitHub Actions runner https://help.github.com/en/actions/reference/software-installed-on-github-hosted-runners as setup.py failed

So we spend multiple minutes installing it from Chocolatey

pywin32/.github/workflows/main.yml

Lines 37 to 38 in 5f47dc1

	- name: Install Windows 8.1 SDK
	run: choco install windows-sdk-8.1

Options:

• Drop 8.1?
• Maybe it's actually on runner & a .bat script somewhere needs to be executed?
• Faster way to install it?

[ofek]

Hmm, found actions/runner-images#842

The Windows 8.1 SDK is no longer available in the Visual Studio installer. Please upgrade your C++ projects to the latest Windows 10 SDK. If you have a hard dependency on 8.1, you can download it from the Windows SDK archive.

considering that it can be installed on runtime and it's a pretty old version, we won't install it by default in the images

[mhammond]

Dropping 8.1 sounds fine to me - the problems solved by insisting on that probably went away when earlier 2.x were dropped. It might make sense to tackle this after I drop 2.7 support though.

[ofek]

Did we drop 8.1 yet?

[mhammond]

yep