polkit-parsing.sh: use the right service name for polkit

The alias polkitd.service was removed in policykit-1 0.113-5, so before the release of Bookworm.

In tests, we can see the message: Failed to restart polkitd.service: Unit polkitd.service not found.

Signed-off-by: Dylan Aïssi dylan.aissi@collabora.com