ansible-pull(role): move ansible-pull reboot logic to script as well

Do this to unify the way these helper scripts get deployed.

roles/ansible_pull/files/ansible-pull-reboot.service

@@ -4,5 +4,4 @@ After=ansible-pull.service
 
 [Service]
 Type=oneshot
-# Reboot, if /var/run/reboot-required or /var/run/ansible-reboot-required exist.
-ExecStart=/usr/bin/bash -c 'if [ -e /var/run/reboot-required ] || [ -e /var/run/ansible-reboot-required ]; then systemctl reboot; fi'
+ExecStart=ansible-pull-reboot

roles/ansible_pull/files/ansible-pull-reboot.sh

@@ -0,0 +1,6 @@
+#!/usr/bin/env bash
+
+# Reboot, if /var/run/reboot-required or /var/run/ansible-reboot-required exist.
+if [ -e /var/run/reboot-required ] || [ -e /var/run/ansible-reboot-required ]; then
+    systemctl reboot
+fi

roles/ansible_pull/tasks/main.yaml

@@ -34,6 +34,7 @@
   become: true
   loop:
     - ansible-pull-successful-run-timestamp-exporter
+    - ansible-pull-reboot
 
 - name: ensure ansible-pull-failure-notify script installation exists
   ansible.builtin.template: