Not updating this one for now, as the one needed by the only package
on-tree that uses it (`calibre`) requires not the latest version but
version 2.1.0, and to build that version and up, we need to have the
`poetry` build system available first.
* 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.
