Update introduction.md (#2208)

* Update introduction.md

Adds Bun in the installation commands.

* Update docs/getting-started/introduction.md

Co-authored-by: Daishi Kato <dai-shi@users.noreply.github.com>

---------

Co-authored-by: Daishi Kato <dai-shi@users.noreply.github.com>

docs/getting-started/introduction.md

@@ -33,9 +33,7 @@ Zustand is available as a package on NPM for use:
 ```bash
 # NPM
 npm install zustand
-
-# Yarn
-yarn add zustand
+# Or, use any package manager of your choice.
 ```
 
 ## First create a store