ci: Temporarily upgrade postgresql-client-common before upgrading.

This works around a failure in the current postgresql-client-common
and postgresql-client-15 packages; it exists primarily to improve
the signal on our CI builds, as the failure is a real failure caused
by the package upgrade process.

.github/workflows/production-suite.yml

@@ -288,6 +288,17 @@ jobs:
           sudo mkdir -p "${dirs[@]}"
           sudo chown -R github "${dirs[@]}"
 
+      - name: Temporarily bootstrap PostgreSQL upgrades
+        # https://chat.zulip.org/#narrow/stream/43-automated-testing/topic/postgres.20client.20upgrade.20failures/near/1640444
+        # On Debian, there is an ordering issue with post-install maintainer
+        # scripts when postgresql-client-common is upgraded at the same time as
+        # postgresql-client and postgresql-client-15.  Upgrade just
+        # postgresql-client-common first, so the main upgrade process can
+        # succeed.  This is a _temporary_ work-around to improve CI signal, as
+        # the failure does represent a real failure that production systems may
+        # encounter.
+        run: sudo apt-get update && sudo apt-get install -y --only-upgrade postgresql-client-common
+
       - name: Upgrade production
         run: sudo /tmp/production-upgrade