Update CHANGELOG.md

Author: daymxn

FirebaseAI/CHANGELOG.md

@@ -1,15 +1,13 @@
-# Unreleased
+# 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.
-
-# 12.2.0
-- [feature] Added support for returning thought summaries, which are synthesized
-  versions of a model's internal reasoning process. (#15096)
+  protection when it becomes available for Firebase AI Logic. (#15099)
 
 # 12.0.0
 - [feature] Added support for Grounding with Google Search. (#15014)