postgres: Add Commvault backup compatibility

This slightly changes the default of the role by always installing postgresql-{{ postgres_version }} (and providing a sensible default for postgres_version), but this is usually the correct thing to do in Debian and a release upgrade requires manual work anyway.

postgres/tasks/main.yml

@@ -53,8 +53,10 @@
   block:
     - name: ensure we have our postgres backup script
       copy:
-        # yamllint disable-line rule:line-length
-        src: "pgbackup{{ '-bullseye' if ansible_distribution_major_version|int(default=99) > 10 else '' }}.sh"
+        src: >-
+          pgbackup{{
+          '-bullseye' if ansible_distribution_major_version|int(default=99) > 10
+          else '' }}.sh
         dest: /usr/local/bin/pgbackup.sh
         owner: root
         group: root