Move postgres backup script and cron to the postgres states

The so-postgres-backup script and its cron were living under
salt/backup/config_backup.sls, which meant the backup script and cron
were deployed independently of whether postgres was enabled/disabled.

- Relocate salt/backup/tools/sbin/so-postgres-backup to
  salt/postgres/tools/sbin/so-postgres-backup so the existing
  postgres_sbin file.recurse in postgres/config.sls picks it up with
  everything else — no separate file.managed needed.
- Remove postgres_backup_script and so_postgres_backup from
  salt/backup/config_backup.sls.
- Add cron.present for so_postgres_backup to salt/postgres/enabled.sls
  and the matching cron.absent to salt/postgres/disabled.sls so the
  cron follows the container's lifecycle.

salt/backup/config_backup.sls

@@ -33,22 +33,3 @@ so_config_backup:
     - month: '*'
     - dayweek: '*'
 
-postgres_backup_script:
-  file.managed:
-    - name: /usr/sbin/so-postgres-backup
-    - user: root
-    - group: root
-    - mode: 755
-    - source: salt://backup/tools/sbin/so-postgres-backup
-
-# Add postgres database backup
-so_postgres_backup:
-  cron.present:
-    - name: /usr/sbin/so-postgres-backup > /dev/null 2>&1
-    - identifier: so_postgres_backup
-    - user: root
-    - minute: '5'
-    - hour: '0'
-    - daymonth: '*'
-    - month: '*'
-    - dayweek: '*'

salt/postgres/disabled.sls

@@ -18,6 +18,12 @@ so-postgres_so-status.disabled:
     - name: /opt/so/conf/so-status/so-status.conf
     - regex: ^so-postgres$
 
+so_postgres_backup:
+  cron.absent:
+    - name: /usr/sbin/so-postgres-backup > /dev/null 2>&1
+    - identifier: so_postgres_backup
+    - user: root
+
 {% else %}
 
 {{sls}}_state_not_allowed:

salt/postgres/enabled.sls

@@ -89,6 +89,17 @@ delete_so-postgres_so-status.disabled:
     - name: /opt/so/conf/so-status/so-status.conf
     - regex: ^so-postgres$
 
+so_postgres_backup:
+  cron.present:
+    - name: /usr/sbin/so-postgres-backup > /dev/null 2>&1
+    - identifier: so_postgres_backup
+    - user: root
+    - minute: '5'
+    - hour: '0'
+    - daymonth: '*'
+    - month: '*'
+    - dayweek: '*'
+
 {% else %}
 
 {{sls}}_state_not_allowed: