docs: change link of v2

Author: baocancode

README.md

@@ -4,7 +4,9 @@ Run [Google Chrome Lighthouse](https://github.com/GoogleChrome/lighthouse) on [A
 ## Versions
 Since 2.x, `lighthouse-lambda` has the same major version of [lighthouse](https://www.npmjs.com/package/lighthouse). For example, `lighthouse-lambda` 3.x will use `lighthouse` 3.x.
 
-This README is for version 3.x. To see version 2.x, visit https://github.com/joytocode/lighthouse-lambda.
+This README is for version 3.x. To see older versions, visit:
+
+- 2.x: https://github.com/joytocode/lighthouse-lambda/tree/archived-v2
 
 ## Installation