Update docker-compose.yml

This get's closer, but it looks like pgadmin overwrites the whole storage directory when it initializes, so the created and linked folder is gone by the time pgadmin is up and running

docker-compose.yml

@@ -69,6 +69,13 @@ services:
       - pgadmin-config:/pgadmin4-config
       - pgadmin:/var/lib/pgadmin
       - *bk-location
+    command: 
+      - /bin/sh
+      - -c
+      - |
+        'mkdir /var/lib/pgadmin/storage/$${PGADMIN_DEFAULT_EMAIL//@/_}/'
+        'ln -s /backups /var/lib/pgadmin/storage/$${PGADMIN_DEFAULT_EMAIL//@/_}/'
+        '/entrypoint.sh'
     depends_on:
       - postgres
       - pgadmin-config