add ai studio link to readme (#2291)

Co-authored-by: Parker Lougheed <[email protected]>

Author: ericwindmill

ai_recipe_generation/README.md

@@ -1,5 +1,7 @@
 This is a demo app created for the Google I/O talk "Gemini API and Flutter: Practical, AI-driven apps with Google AI tools"
 
+Check out the [the prompt we used on Google AI Studio](https://aistudio.google.com/app/prompts/1RsTAt6_N8BPhXbrrd8gSJcdeuYV834kf).
+
 ## Running the app 
 
 Before running the app: