Addon-docs: Change 2nd argument of transformSource to the storyContext

[phated]

Issue: N/A

What I did

Similar to #12178, the transformSource method option in addon-docs was receiving the storyId instead of the entire context.

This is slightly breaking because it changes the 2nd argument to be the entire context instead of just the story id. However, I think this is okay because an end-user can destructure the story id from the context, and the 2nd parameter also was only documented in one recipe and not tested at all.

This will also bring the transformSource method inline with the definition in #12178.

How to test

• Is this testable with Jest or Chromatic screenshots? Yes, added jest tests
• Does this need a new example in the kitchen sink apps? No; however, I'll be able to expand on this work in the future to add a cool example to the kitchen sink!
• Does this need an update to the documentation? Updated the recipe.

If your answer is yes to any of these, please make sure to include it in your PR.