Onboard bertptrs as Package Maintainer

Bert has previously been a Junior Package Maintainer, but the two
month period is now long up and their changes in the packaging ecosystem
looked good and their community engagement is awesome.

Signed-off-by: Christian Heusel <christian@heusel.eu>

group_vars/all/archusers.yml

@@ -181,6 +181,7 @@ arch_users:
     email: "bertptrs@archlinux.org"
     ssh_key: bertptrs_ganymede.pub
     groups:
+      - packager
       - junior-packager
     additional_ssh_keys:
       - name: bertptrs_rhea.pub