While switching to 3.10 as default, lets just drop the 3.9 versions of these packages.
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Checked runtime and build dependencies, but only tried a build of `hatchling` locally. I'll merge as is, and if something breaks, will fix later on.
* python3.8: bulk removal of now obsolete "_python38" packages.
Done via scripting. No functional change intended or expected.
Some manual tweaks will follow.
* python3.8: further manual tweaks after bulk-3.8-removal.
Unlike the previous commit with automated changes,
I've tested builds for *these* recipes in beta4 64 bits.
