feat: add option for external docker networks

defaults/main.yml

@@ -11,6 +11,7 @@ zigbee2mqtt_service_stopped: False
 #   - name: default
 #     # optional network driver, defaults to 'bride'
 #     driver: host
+#     external: false
 # @end
 zigbee2mqtt_networks:
   - name: default

templates/services/zigbee2mqtt_compose.yml.j2

@@ -81,6 +81,10 @@ volumes:
 networks:
   {% for network in zigbee2mqtt_networks %}
   {{ network.name }}:
+    {% if network.external | default(False) | bool %}
+    external: true
+    {% else %}
     driver: {{ network.backend | default("bridge") }}
+    {% endif %}
   {% endfor %}
 {% endif %}