Update volume removal command in installation guide

Removed 'oneclickvirt-config' from volume removal command.

Author: spiritLHLS

docs/guide/oneclickvirt/oneclickvirt_install.md

@@ -131,7 +131,7 @@ docker cp config.yaml oneclickvirt:/app/config.yaml
 
 ```shell
 docker rm -f oneclickvirt
-docker volume rm oneclickvirt-data oneclickvirt-storage oneclickvirt-config
+docker volume rm oneclickvirt-data oneclickvirt-storage
 ```
 
 然后删除原始的镜像：