Add docs link

Author: rachmari

README.md

@@ -1,6 +1,6 @@
 # Hello world JavaScript action
 
-This action prints "Hello World" or "Hello" + the name of a person to greet to the log.
+This action prints "Hello World" or "Hello" + the name of a person to greet to the log. To learn how this action was built, see "[Creating a JavaScript action](https://help.github.com/en/articles/creating-a-javascript-action)" in the GitHub Help documentation.
 
 ## Inputs