fix flaky tests on python 3.11

[terriko]

• related: ci: test on Python 3.11 #2419

In enabling Python 3.11 in our CI system, @Molkree discovered that some of our tests are a bit flaky on python 3.11 (as in, they fail sometimes but not every run). Strangely, some of these are ones that also gave us trouble on python 3.7, but they've been working consistently on python 3.8-3.10.

For the moment, the following tests are disabled on 3.11:

If anyone can figure out why they're flaky and how they could be improved, that would be very helpful.

• test_extract_file_deb
• test_extract_file_ipk
• scanner on libvncserver1_0.9.12+dfsg-9ubuntu0.3_amd64.deb

One thing they all have in common is extraction using ar but there's many other tests that use .deb files at least so it's probably not going to be just that or that could be a red herring. Not sure yet.

Please note anything you find in the comments here even if you don't have a complete solution. Due to the sporadic nature of the fails, it may take a while and several people's worth of data to figure out what's going awry.

[terriko]

I haven't seen this behaviour in a long time, so I'm going to close this.