Remove volume mounts from app json definition

app.json

@@ -3,11 +3,6 @@
   "description": "Gitea is a painless self-hosted Git service.",
   "repository": "https://gitlab.com/autonomic-cooperative/coop-cloud/gitea",
   "dokku": {
-    "plugins": ["mariadb"],
-    "volumes": [
-      { "host": "/var/lib/gitea", "app": "/data" },
-      { "host": "/etc/timezone", "app": "/etc/timezone:ro" },
-      { "host": "/etc/localtime", "app": "/etc/localtime:ro" }
-    ]
+    "plugins": ["mariadb"]
   }
 }