container: set TZ variable

roles/container/defaults/main.yml

@@ -2,3 +2,5 @@
 
 docker_host_user: false
 docker_volume_type: named
+
+timezone: Etc/UTC

roles/container/meta/argument_specs.yml

@@ -117,3 +117,8 @@ argument_specs:
         type: list
         required: false
         elements: str
+      timezone:
+        description: "Timezone set in the TZ env var"
+        type: str
+        required: false
+        default: Etc/UTC

roles/container/tasks/main.yml

@@ -66,7 +66,7 @@
     mounts: "{{ docker_volume_definition }}"
     published_ports: "{{ container_published_ports + docker_published_ports }}"
     labels: "{{ traefik_labels | default(omit) }}"
-    env: "{{ docker_env | combine(docker_additional_env) }}"
+    env: "{{ docker_env | combine(docker_additional_env) | combine({'TZ': timezone}) }}"
     entrypoint: "{{ docker_entrypoint | default(omit) }}"
     restart_policy: always
     network_mode: "{{ docker_network_mode | default(omit) }}"