The Python toolchain we build is now version `3.10.11`, the last `3.10` with
an official Windows installer for `pack-cpython.sh` to extract.
The Debian 11 bootstrap task goes away because bullseye ships nothing newer
than Python 3.9. The supported build hosts are the current stable and testing
releases, Debian 13 and 14, which keep their tasks. Rocky Linux 9 installs
`python3.11` and puts it first on `PATH` as `python3`, since its `python3`
package stays at 3.9.
The Linux test tasks run on the fetched CI Python, so the `dbus-python`, `pygobject`
and `pycairo` wheel tasks now build against it and are named by Python version.
The distro keyed wheel tasks and images were unused and were removed.
Differential Revision: https://phabricator.services.mozilla.com/D322844
Alex Hochheiden
f1709d5ed1