Update borgmatic 1.8.3 -> 1.8.4

requirements.yml

@@ -4,7 +4,7 @@
   version: v1.0.0-1
   name: auxiliary
 - src: git+https://gitlab.com/etke.cc/roles/backup_borg.git
-  version: v1.2.6-1.8.3-0
+  version: v1.2.6-1.8.4-0
 - src: git+https://github.com/devture/com.devture.ansible.role.container_socket_proxy.git
   version: v0.1.1-2
 - src: git+https://github.com/devture/com.devture.ansible.role.docker_sdk_for_python.git