rclone: fix configuration saving

rclone: fix configuration saving

The following error occurs when creating storage configuration in WEBUI:
```
Failed to save config after 10 tries: failed to create temp file for new config: open /etc/rclone/rclone.conf4258227003: permission denied
```

we should set the owner of the parent directory of the configuration
file to rclone.

Signed-off-by: Liangbin Lian <redacted>
[split chown command, wrap commit message]
Signed-off-by: Tianling Shen <redacted>