Code review comment for ~bluca/ubuntu/+source/systemd:jammy_repart

Thank you Luca, for splitting out the new files into its own systemd-repart binary.

I've staged the changes to provide an upgrade path in Kinetic++:
https://git.launchpad.net/~ubuntu-core-dev/ubuntu/+source/systemd/commit/?h=ubuntu-kinetic&id=2281670aa8007179170d5cc485bb94e3bbc3b63c

Furthermore, I've re-wrote d/changelog, using "gbp dch", as we usually do in Ubuntu.
And modified d/t/control to add the new binary as a test dependency to the "upstream-2" test case, this avoids skipping TEST-58-REPART.

I've rolled the change into the currently pending Jammy SRU at:
https://git.launchpad.net/~ubuntu-core-dev/ubuntu/+source/systemd

For reference, the new "libssl-dev" build dependency is required to allow for a hmac calculation in sd-repart. Alternatively, this commit could be backported to avoid the dependency: https://github.com/systemd/systemd/commit/ade99252e2cdd9eeff78566789008996d27e4dc0