mention base image in docs

Author: phm07

docs/tutorials/setup-hcloud-cli.md

@@ -66,6 +66,12 @@ If you want to use (and persist) your configuration, you can mount it to `/confi
 docker run --rm -v ~/.config/hcloud/cli.toml:/config.toml hetznercloud/cli:latest <command>
 ```
 
+The image is based on Alpine Linux, so a shell is available in the image. You can use it to run commands interactively:
+
+```bash
+docker run -it --rm --entrypoint /bin/sh hetznercloud/cli:latest
+```
+
 ---
 
 > [!WARNING]