add handlers for docker role (unused yet)

roles/docker/handlers/main.yml

@@ -0,0 +1,18 @@
+---
+# TODO this is yet unused
+- name: test docker setup
+  become: true
+  community.docker.docker_container:
+    name: test-docker
+    image: hello-world
+    state: started
+  register: docker_test
+  when: docker_install is changed
+
+- name: remove test container
+  become: true
+  community.docker.docker_container:
+    name: test-docker
+    image: hello-world
+    state: absent
+  when: docker_install is changed