docs(vite-plugin-react-router): fix npm i typo (#478)

This might work but it's weird.

Author: serhalp

packages/vite-plugin-react-router/README.md

@@ -8,7 +8,7 @@ To deploy a React Router 7+ site to Netlify, install this package:
 ## How to use
 
 ```sh
-npm --save-dev install @netlify/vite-plugin-react-router
+npm install --save-dev @netlify/vite-plugin-react-router
 ```
 
 and include the Netlify plugin in your `vite.config.ts`: