burp-client: Switch from cron to systemd timer

systemd timer units are supported on all relevant OS versions now.
There is no longer any reason to use cron.

roles/burp-client/files/burp-backup.cron

@@ -1 +0,0 @@
-18,48 * * * * root /usr/sbin/burp -a t -Q

roles/burp-client/files/burp-backup.fcron

@@ -1 +0,0 @@
-@mail(no) 30 /usr/sbin/burp -a t

roles/burp-client/files/burp-backup.service

@@ -0,0 +1,27 @@
+# vim: set ft=systemd :
+[Unit]
+Description=BURP client
+After=network-online.target
+Wants=network-online.target
+
+[Service]
+Type=exec
+ExecStart=/usr/sbin/burp -a t -Q
+SuccessExitStatus=3
+CapabilityBoundingSet=CAP_BLOCK_SUSPEND CAP_DAC_OVERRIDE CAP_DAC_READ_SEARCH
+CapabilityBoundingSet=CAP_FOWNER CAP_LEASE CAP_SETGID CAP_SETUID
+NoNewPrivileges=yes
+PrivateDevices=yes
+PrivateTmp=yes
+ProcSubset=pid
+ProtectClock=yes
+ProtectControlGroups=yes
+ProtectHostname=yes
+ProtectKernelLogs=yes
+ProtectKernelModules=yes
+ProtectKernelTunables=yes
+ProtectProc=noaccess
+ProtectSystem=full
+SystemCallArchitectures=native
+SystemCallFilter=@system-service @privileged @mount
+SystemCallFilter=~@clock @debug @module @reboot @swap

roles/burp-client/files/burp-backup.timer

@@ -0,0 +1,10 @@
+# vim: set ft=systemd :
+[Unit]
+Description=Periodically run BURP client
+
+[Timer]
+OnCalendar=*:18
+OnCalendar=*:48
+
+[Install]
+WantedBy=timers.target

roles/burp-client/handlers/main.yml

@@ -1,2 +1,3 @@
-- name: reload system crontab
-  command: /usr/libexec/check_system_crontabs -v -i
+- name: reload systemd
+  systemd:
+    daemon_reload: true

roles/burp-client/tasks/main.yml

@@ -49,8 +49,28 @@
   command:
     burp -c /etc/burp/burp.conf -g
     creates=/etc/burp/ssl_cert-client.pem
-- name: ensure automatic backup is scheduled
+
+- name: ensure auto backup systemd units are installed
   copy:
-    src={{ burp_backup_crontab }}
-    dest=/etc/cron.d/burp-backup
-    mode=0644
+    src: '{{ item }}'
+    dest: /etc/systemd/system/
+    mode: u=rw,go=r
+  loop:
+  - burp-backup.service
+  - burp-backup.timer
+  notify:
+  - reload systemd
+  tags:
+  - systemd
+- name: ensure auto backup timer is enabled
+  systemd:
+    name: burp-backup.timer
+    enabled: true
+    state: started
+  tags:
+  - service
+
+- name: ensure legacy burp crontab file is removed
+  file:
+    path: /etc/cron.d/burp-backup
+    state: absent