Update CHANGELOG.md

Author: daymxn

FirebaseAI/CHANGELOG.md

@@ -1,13 +1,10 @@
 # 12.2.0
 - [feature] Added support for returning thought summaries, which are synthesized
   versions of a model's internal reasoning process. (#15096)
-- [feature] Added a new configuration option to use limited-use App
-  Check tokens for attesting Firebase AI Logic requests. This enhances
-  security against replay attacks. To use this feature, configure it
-  explicitly via the new `useLimitedUseAppCheckTokens` parameter when
-  initializing `FirebaseAI`. We recommend migrating to limited-use
-  tokens now, so your app will be ready to take advantage of replay
-  protection when it becomes available for Firebase AI Logic. (#15099)
+- [feature] Added support for limited-use tokens with Firebase App Check. These short-lived tokens 
+  provide greater protection for the APIs that give you access to Gemini and Imagen models. Learn 
+  how to [enable usage of limited-use tokens](https://firebase.google.com/docs/ai-logic/app-check).
+  (#15099)
 
 # 12.0.0
 - [feature] Added support for Grounding with Google Search. (#15014)