update analyzer constraint (#278)

Author: FaFre

pkgs/shelf_router_generator/pubspec.yaml

@@ -9,7 +9,7 @@ environment:
   sdk: '>=2.12.0 <3.0.0'
 
 dependencies:
-  analyzer: '>=2.0.0 <4.0.0'
+  analyzer: '>=2.0.0 <5.0.0'
   build: ^2.0.0
   build_config: ^1.0.0
   code_builder: ^4.0.0