Revert internal network change (see https://git.autonomic.zone/coop-cloud/organising/issues/62)

compose.yml

@@ -56,7 +56,7 @@ services:
     networks:
       - internal
     deploy:
-      labels: ['coop-cloud.${STACK_NAME}.db.version=11.12-alpine-714248ba']
+      labels: ['coop-cloud.${STACK_NAME}.db.version=11.12-alpine-09c7c402']
 volumes:
   postgres:
   codimd_uploads:
@@ -68,7 +68,6 @@ networks:
   proxy:
     external: true
   internal:
-    internal: true
 configs:
   entrypoint_conf:
     name: ${STACK_NAME}_entrypoint_${ENTRYPOINT_CONF_VERSION}