Update TOC based on the new content

Author: ahangarha

README.md

@@ -64,10 +64,10 @@ Read the [full review here](https://clutch.co/profile/shakacode#reviews?sort_by=
   - [Camelize Props](#camelize-props)
   - [Changing Component Templates](#changing-component-templates)
 - [Upgrading](#upgrading)
+  - [2.7 to 3.0](#27-to-30)
   - [2.3 to 2.4](#23-to-24)
 - [Common Errors](#common-errors)
   - [Getting warning for `Can't resolve 'react-dom/client'` in React < 18](#getting-warning-for-cant-resolve-react-domclient-in-react--18)
-  - [During installation](#during-installation)
   - [Undefined Set](#undefined-set)
   - [Using TheRubyRacer](#using-therubyracer)
   - [HMR](#hmr)