hw4: finalize selenoid and ansible workflow with citrus tests

ansible/roles/docker/tasks/main.yml

@@ -0,0 +1,32 @@
+---
+- name: Check whether docker CLI is already available
+  ansible.builtin.command: docker --version
+  register: docker_cli_check
+  changed_when: false
+  failed_when: false
+
+- name: Install Docker packages when docker is missing
+  ansible.builtin.apt:
+    name:
+      - docker.io
+      - docker-compose-v2
+    state: present
+  when: docker_cli_check.rc != 0
+
+- name: Enable Docker service when installed by role and systemd is available
+  ansible.builtin.service:
+    name: docker
+    state: started
+    enabled: true
+  when:
+    - docker_cli_check.rc != 0
+    - ansible_service_mgr == "systemd"
+
+- name: Add current ansible user to docker group
+  ansible.builtin.user:
+    name: "{{ ansible_user }}"
+    groups: docker
+    append: true
+  when:
+    - ansible_user is defined
+    - docker_cli_check.rc != 0