Fix conclusion header level

2025-06-05_zsh-gnu-stow.md

@@ -385,7 +385,7 @@ configurations when multiple connections will be attaching the same `tmux` sessi
 This also highlights that I still do use `bash` for most of my remote connections, since `bash`
 is available by default on every Linux distribution I've come across and `zsh` is far less ubiquitous.
 
-### Conclusion
+## Conclusion
 
 I don't think my shell configuration will ever be "done", but I've reached a point where I'm
 satisfied for now. GNU `stow` has simplified my dotfile management and made it easier to