Comment 4 for bug 1968367

Hi Paul (@vultaire) we could not use `charm-python-packages`, since this is reactive charm
and we are using reactive plugin.

However we potentially could use `build-packages` and define `fabric` (`cryptography`) in
wheelhouse.txt instead of installing in with layers. However I could not make it work, so for
now I proposed only add `pkg-config` and disabling `include_system_packages`.