hghave: we might need py310 and py311 at some point Some tests are already showing slightly different results on Python 3.11. The better idea would be to make them more portable, but if that's not possible, now we can use hghave detection for certain lines. I wonder if there will ever be Python 31.0 and 31.1 though.

hghave: detect Python 3.10 and 3.11 as well Noticed because test-contrib-relnotes.t was skipped.