puppet: Run delete-old-unclaimed-attachments in archive cron file.

After reflecting a bit on the last commit, I think it's substantially
easier to understand what's happening for these two tasks to be
defined in the same file, because we want the timing to be different
to avoid potential races.

puppet/zulip/files/cron.d/archive-messages

@@ -5,3 +5,6 @@ USER=zulip
 # Daily cron job for retention policy - archives existing messages based on the policy
 # and cleans expired entries from the archive.
 0 6 * * * zulip /home/zulip/deployments/current/manage.py archive_messages >/dev/null
+# Daily cron job for cleaning up old, unclaimed attachments and their corresponding files.
+# Ideally should not run at the same time as the previous job, to avoid races.
+0 5 * * * zulip /home/zulip/deployments/current/manage.py delete_old_unclaimed_attachments -f >/dev/null

puppet/zulip/files/cron.d/delete-old-unclaimed-attachments

@@ -1,6 +0,0 @@
-SHELL=/bin/bash
-PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
-USER=zulip
-
-# Daily cronjob for cleaning up old, unclaimed attachments and their corresponding files.
-0 6 * * * zulip /home/zulip/deployments/current/manage.py delete_old_unclaimed_attachments -f >/dev/null

puppet/zulip/manifests/app_frontend_once.pp

@@ -67,14 +67,6 @@ class zulip::app_frontend_once {
     source => 'puppet:///modules/zulip/cron.d/archive-messages',
   }
 
-  file { '/etc/cron.d/delete-old-unclaimed-attachments':
-    ensure => file,
-    owner  => 'root',
-    group  => 'root',
-    mode   => '0644',
-    source => 'puppet:///modules/zulip/cron.d/delete-old-unclaimed-attachments',
-  }
-
   file { '/etc/cron.d/clearsessions':
     ensure => file,
     owner  => 'root',