Add cronjob to prune docker system once per day

tasks/main.yml

@@ -36,7 +36,7 @@
         groups: docker
         append: yes
 
-    - name: Deply ansible script to run inside Docker
+    - name: Deploy ansible script to run inside Docker
       template:
         src: ansible.sh
         dest: /usr/local/bin/ansible
@@ -44,4 +44,14 @@
         group: root
         mode: 0755
 
+    - name: Cleanup Docker once per day
+      cron:
+        name: Cleanup Docker
+        hour: 23
+        minute: 55
+        job: /usr/bin/docker system prune -f > /dev/null 2>&1
+        disabled: '{{ crons_disabled|default(false) }}'
+      tags:
+        - cron
+
   when: not excluded_roles or "gitlab-runner" not in excluded_roles