Add matrix_nginx_proxy_container_network variable

roles/custom/matrix-nginx-proxy/templates/systemd/matrix-nginx-proxy.service.j2

@@ -24,7 +24,7 @@ ExecStartPre={{ devture_systemd_docker_base_host_command_docker }} create \
 			--cap-drop=ALL \
 			--read-only \
 			--tmpfs=/tmp:rw,noexec,nosuid,size={{ matrix_nginx_proxy_tmp_directory_size_mb }}m \
-			--network={{ matrix_docker_network }} \
+			--network={{ matrix_nginx_proxy_container_network }} \
 			{% if matrix_nginx_proxy_container_http_host_bind_port %}
 			-p {{ matrix_nginx_proxy_container_http_host_bind_port }}:8080 \
 			{% endif %}