Pin baseflow_plugin_template to 2.1.2 to fix example build failure

Author: wangyongqi

permission_handler_android/example/pubspec.yaml

@@ -5,7 +5,7 @@ environment:
   sdk: ^3.7.0
 
 dependencies:
-  baseflow_plugin_template: ^2.1.2
+  baseflow_plugin_template: 2.1.2
   flutter:
     sdk: flutter
   permission_handler_platform_interface: ^4.2.0