update readme with changes

README.md

@@ -2,7 +2,7 @@
   <a href="https://github.com/actions/checkout"><img alt="GitHub Actions status" src="https://github.com/actions/checkout/workflows/test-local/badge.svg"></a>
 </p>
 
-# Checkout V2
+# Checkout V3
 
 This action checks-out your repository under `$GITHUB_WORKSPACE`, so your workflow can access it.
 
@@ -14,21 +14,8 @@ When Git 2.18 or higher is not in your PATH, falls back to the REST API to downl
 
 # What's new
 
-- Improved performance
+- Updated to the node16 runtime by default as node12
-  - Fetches only a single commit by default
+  - This requires a minimum [Actions Runner](https://github.com/actions/runner/releases/tag/v2.285.0) version of v2.285.0 to run, which is by default available in GHES 3.4 or later.
-- Script authenticated git commands
-  - Auth token persisted in the local git config
-- Supports SSH
-- Creates a local branch
-  - No longer detached HEAD when checking out a branch
-- Improved layout
-  - The input `path` is always relative to $GITHUB_WORKSPACE
-  - Aligns better with container actions, where $GITHUB_WORKSPACE gets mapped in
-- Fallback to REST API download
-  - When Git 2.18 or higher is not in the PATH, the REST API will be used to download the files
-  - When using a job container, the container's PATH is used
-
-Refer [here](https://github.com/actions/checkout/blob/v1/README.md) for previous versions.
 
 # Usage