Update readme sample in creating-a-javascript-action.md (#21377)

content/actions/creating-actions/creating-a-javascript-action.md

@@ -141,29 +141,31 @@ In your `hello-world-javascript-action` directory, create a `README.md` file tha
 - Environment variables the action uses.
 - An example of how to use your action in a workflow.
 
-```markdown{:copy}
+````markdown{:copy}
 # Hello world javascript action
 
 This action prints "Hello World" or "Hello" + the name of a person to greet to the log.
 
 ## Inputs
 
-## `who-to-greet`
+### `who-to-greet`
 
 **Required** The name of the person to greet. Default `"World"`.
 
 ## Outputs
 
-## `time`
+### `time`
 
 The time we greeted you.
 
 ## Example usage
 
+```yaml
 uses: actions/hello-world-javascript-action@v1.1
 with:
   who-to-greet: 'Mona the Octocat'
 ```
+````
 
 ## Commit, tag, and push your action to GitHub