puppet: Remove all purged/absent blocks known to have run already.

It is not possible to have upgraded from 4.x to this version without
having run puppet at least once, since there are no shared OS versions
in between them.  Remove these `absent`/`purged` blocks which we know
to have already been run.

puppet/zulip/manifests/app_frontend_base.pp

@@ -118,16 +118,6 @@ class zulip::app_frontend_base {
     source  => 'puppet:///modules/zulip/nginx/zulip-include-frontend/uploads-internal.conf',
   }
 
-  file { [
-    # TODO/compatibility: Removed 2021-04 in Zulip 4.0; these lines can
-    # be removed once one must have upgraded through Zulip 4.0 or higher
-    # to get to the next release.
-    '/etc/nginx/zulip-include/uploads.route',
-    '/etc/nginx/zulip-include/app.d/thumbor.conf',
-  ]:
-    ensure => absent,
-  }
-
   # This determines whether we run queue processors multithreaded or
   # multiprocess.  Multiprocess scales much better, but requires more
   # RAM; we just auto-detect based on available system RAM.

puppet/zulip/manifests/postgresql_backups.pp

@@ -25,19 +25,6 @@ class zulip::postgresql_backups {
     ],
   }
 
-  # Zulip 4.x and before used the `cron` resource here, which placed
-  # this in the postgres user's crontab, which was not discoverable.
-  # Removed 2021-11 in version 5.0; these lines can be removed when we
-  # drop support for upgrading from Zulip 4 or older.
-  cron { 'pg_backup_and_purge':
-    ensure      => absent,
-    command     => '/usr/local/bin/pg_backup_and_purge',
-    environment => 'PATH=/bin:/usr/bin:/usr/local/bin',
-    hour        => 2,
-    minute      => 0,
-    target      => 'postgres',
-    user        => 'postgres',
-  }
   file { '/etc/cron.d/pg_backup_and_purge':
     ensure  => present,
     owner   => 'root',

puppet/zulip/manifests/postgresql_base.pp

@@ -75,13 +75,6 @@ class zulip::postgresql_base {
   $pgroonga = zulipconf('machine', 'pgroonga', false)
   if $pgroonga {
     # Needed for optional our full text search system
-
-    # Removed 2020-12 in version 4.0; these lines can be removed when
-    # we drop support for upgrading from Zulip 3 or older.
-    package{"${postgresql}-pgroonga":
-      ensure => purged,
-    }
-
     package{"${postgresql}-pgdg-pgroonga":
       ensure  => latest,
       require => [

puppet/zulip/manifests/profile/rabbitmq.pp

@@ -8,12 +8,6 @@ class zulip::profile::rabbitmq {
     $erlang,
     'rabbitmq-server',
   ]
-  # Removed 2020-09 in version 4.0; these lines can be removed in
-  # Zulip version 5.0 and later.
-  file { ['/etc/cron.d/rabbitmq-queuesize', '/etc/cron.d/rabbitmq-numconsumers']:
-    ensure => absent,
-  }
-
 
   group { 'rabbitmq':
     ensure => present,

puppet/zulip/manifests/supervisor.pp

@@ -25,20 +25,6 @@ class zulip::supervisor {
     notify  => Service[$supervisor_service],
   }
 
-  # These files were moved from /etc/supervisor/conf.d/ into a zulip/
-  # subdirectory in 2020-10 in version 4.0; these lines can be removed
-  # in Zulip version 5.0 and later.
-  file { [
-    "${system_conf_dir}/cron.conf",
-    "${system_conf_dir}/nginx.conf",
-    "${system_conf_dir}/smokescreen.conf",
-    "${system_conf_dir}/thumbor.conf",
-    "${system_conf_dir}/zulip.conf",
-    "${system_conf_dir}/zulip_db.conf",
-    ]:
-    ensure => absent,
-  }
-
   # In the docker environment, we don't want/need supervisor to be
   # started/stopped /bin/true is used as a decoy command, to maintain
   # compatibility with other code using the supervisor service.