[objective_c] Prepare to publish v9.2.1 (#2826)

Author: liamappelbe

pkgs/objective_c/CHANGELOG.md

@@ -1,7 +1,8 @@
-## 9.2.0+1
+## 9.2.1
 
 - Fix [bug](https://github.com/dart-lang/native/issues/2824) where the build
   hook was trying to access the code config if it was not provided.
+- Bump minimum Dart version to 3.10.0.
 
 ## 9.2.0
 

pkgs/objective_c/pubspec.yaml

@@ -4,7 +4,7 @@
 
 name: objective_c
 description: 'A library to access Objective C from Flutter that acts as a support library for package:ffigen.'
-version: 9.2.0+1
+version: 9.2.1
 repository: https://github.com/dart-lang/native/tree/main/pkgs/objective_c
 issue_tracker: https://github.com/dart-lang/native/issues?q=is%3Aissue+is%3Aopen+label%3Apackage%3Aobjective_c
 
@@ -15,7 +15,7 @@ topics:
   - codegen
 
 environment:
-  sdk: '>=3.9.0-21.0.dev <4.0.0'
+  sdk: '>=3.10.0 <4.0.0'
 
 dependencies:
   code_assets: ^0.19.0