devtools 20230105-1 enables the debug option by default.

A follow-up commit will remove debug from alongside other options.

Cf. https://gitlab.archlinux.org/archlinux/rfcs/-/blob/master/rfcs/0011-store-source-signing-keys.rst

These are not necessary according to the current CMake guidelines and indeed
the binaries stay the same without them.

This release was only made for technical reasons and contains no changes
relative to version 3.2.9, but bump the version number nevertheless to stay in
sync with upstream.

https://matrix.org/blog/2021/12/13/disclosure-buffer-overflow-in-libolm-and-matrix-js-sdk/

"make olm-python3" is a no-op now, so directly use setup.py instead.

To test the library auto-generated by CFFI without installing the Python
package, the "build/lib.<platform>-<pyver>" (e.g. "build/lib.linux-x86_64-3.8")
directory must be added to the Python path. This is more elegant than the
previous version of running the CFFI helper "olm_build.py" to recreate the
library in the current directory where it can be found directly by Python: it
avoids compiling in check() and makes sure that we test exactly the same library
that is going to get installed by the package.