Update caddy/content.md with simplification of persisting data volume

caddy/content.md

@@ -144,10 +144,7 @@ services:
 
 volumes:
   caddy_data:
-    external: true
   caddy_config:
 ```
 
-Defining the data volume as [`external`](https://docs.docker.com/compose/compose-file/compose-file-v3/#external) makes sure `docker-compose down` does not delete the volume. You may need to create it manually using `docker volume create [project-name]_caddy_data`.
-
 Graceful reloads can then be conducted via `docker compose exec -w /etc/caddy caddy caddy reload`.