chore: bump flutter sdk requirements

Author: sifferhans

bccm_core/pubspec.yaml

@@ -4,8 +4,8 @@ version: 0.0.1
 homepage:
 
 environment:
-  sdk: ">=3.1.0 <4.0.0"
-  flutter: ">=1.17.0"
+  sdk: ">=3.8.0 <4.0.0"
+  flutter: ">=3.35.0"
 
 dependencies:
   app_links: ^6.3.2