Ensure docker is installed on additional JVBs (fixes #2706)

This contribution is provided by GRNET S.A. (grnet.gr).

group_vars/jitsi_jvb_servers

@@ -7,3 +7,5 @@ devture_systemd_service_manager_services_list_auto: |
   {{
     ([{'name': (jitsi_identifier + '-jvb.service'), 'priority': 4100, 'groups': ['matrix', 'jitsi', 'jitsi-jvb']}] if jitsi_enabled else [])
   }}
+
+matrix_playbook_docker_installation_enabled: true

jitsi_jvb.yml

@@ -7,6 +7,26 @@
     - role: galaxy/com.devture.ansible.role.playbook_help
     - role: galaxy/com.devture.ansible.role.systemd_docker_base
 
+    - when: matrix_playbook_docker_installation_enabled | bool
+      role: galaxy/geerlingguy.docker
+      vars:
+        docker_install_compose: false
+      tags:
+        - setup-docker
+        - setup-all
+        - setup-additional-jitsi-jvb
+        - install-docker
+        - install-all
+
+    - when: devture_docker_sdk_for_python_installation_enabled | bool
+      role: galaxy/com.devture.ansible.role.docker_sdk_for_python
+      tags:
+        - setup-docker
+        - setup-all
+        - setup-additional-jitsi-jvb
+        - install-docker
+        - install-all
+
     - custom/matrix-base
     - galaxy/jitsi
     - custom/matrix-common-after