change nushell shortcut to use def instead of alias
Fix
@@ -33,7 +33,7 @@ If you prefer to manage the function sourcing yourself, or to automate the insta
As a shortcut for [Nushell](https://www.nushell.sh/), define the following alias:
- alias br [] { broot | trim | cd $it }
+ def br [] { broot | trim | cd $it }
# `br` alias for Xonsh shell
