test: GitHub Actions add Windows to the testing

[cclauss]

@joaocgreis This might be of interest to you.

Checklist

• npm install && npm test passes
• tests are included
• documentation is changed or added
• commit message follows commit guidelines

Description of change

[gengjiawen]

Windows test still failed

[cclauss]

Yes. I am not a Windows guy and I do not understand how to fix test_BinaryNamesWindows()
https://github.com/nodejs/node-gyp/pull/1996/checks?check_run_id=350074778#step:6:23

[joaocgreis]

@cclauss isn't this similar to what happened in Travis, the VS version is more recent than the one supported by our gyp version? If this is the case, a good way to fix is to set the MSVS variables similarly to Travis:

node-gyp/.travis.yml

Line 106 in 5a729e8

- GYP_MSVS_VERSION=2015 GYP_MSVS_OVERRIDE_PATH="C:\\Dummy" python -m pytest

[cclauss]

Powershell says The term 'GYP_MSVS_VERSION=2015' is not recognized as the name of a cmdlet, function, script file, or operable program.

[cclauss]

@joaocgreis Using shell: bash along with your suggestion enables the Windows tests to pass. Thanks much!