Remove unittest.makeSuite, gone from Python 3.13

[hroncok]

See https://docs.python.org/3.13/whatsnew/3.13.html

"""
Removed the following unittest functions, deprecated in Python 3.11:

unittest.findTestCases()
unittest.makeSuite()
unittest.getTestCaseNames()

"""

The removed call does not seem to have any effect when the file is executed directly, run trough unittest discover or pytest.

[takluyver]

Thanks!

It looks like the CI failures are just down to old Python versions no longer available on Github actions. If necessary, we could get at least some of those back by running on older versions of Ubuntu (like this example), but I don't think that's especially necessary. Ptyprocess is pretty stable, so I think it's fine to leave anyone stuck on an older Python with an older Ptyprocess as well.

So I'll make a separate PR updating the minimum support Python to 3.7, as that's the oldest that it's no extra effort to test. 3.7 itself is EOL as of ~4 months ago, but unless we want to use a newer Python feature it's basically free to leave it supported.

[takluyver]

I'll do a quick close & reopen of this to re-run the tests, just to be sure I'm not overlooking another issue.

[takluyver]

Thanks @hroncok !

[jquast]

Thanks @takluyver, I fully support py2.7 testing, I also am supporting python 2.7 in my 'wcwidth' and 'blessed' libraries with github action, too.

[takluyver]

Oh, sorry, I removed 2.7 testing in #76. Do you want me to add it back? I'm not using 2.7 for anything myself, and it stopped getting any further bugfix releases a few years ago, so it doesn't feel particularly important to keep supporting it.