Add package signatures back to repo desc files and fix various other issues

With pacman 6.1 the addition of package signatures to the repository sync database "desc" file has been demoted to the --include-sigs options.

We want signatures in our sync database because it allows us to search for signer of a package using pacman -Sii.

Replace the use of sq with rsop as the SOP interfaces are not changing and sq breaks on every release.

Fix various issues wrt GnuPG >= 2.4 and pacman >= 6.1.