Add docker_prune sample to remove everything, including non-dangling images (#52744)

* Update docker_prune.py

##### SUMMARY
Add example to remove everything, including non-dangling images


##### ISSUE TYPE
- Docs Pull Request

+label: docsite_pr

* fix indentation

* Update lib/ansible/modules/cloud/docker/docker_prune.py

Co-Authored-By: nicosingh <nicolas.singh@gmail.com>

lib/ansible/modules/cloud/docker/docker_prune.py

@@ -105,6 +105,16 @@ EXAMPLES = '''
     networks: yes
     volumes: yes
     builder_cache: yes
+
+- name: Prune everything (including non-dangling images)
+  docker_prune:
+    containers: yes
+    images: yes
+    images_filters:
+      dangling: false
+    networks: yes
+    volumes: yes
+    builder_cache: yes
 '''
 
 RETURN = '''