fix(graphql_flutter): upgrade connectivity_plus

2 important commits:
v6.0.2: fluttercommunity/plus_plugins#2763
v6.0.3: fluttercommunity/plus_plugins#2836

Author: hantrungkien

packages/graphql_flutter/pubspec.yaml

@@ -15,7 +15,7 @@ dependencies:
   meta: ^1.7.0
   path_provider: ^2.0.1
   path: ^1.8.0
-  connectivity_plus: ^6.0.1
+  connectivity_plus: ^6.0.3
   hive: ^2.0.0
   plugin_platform_interface: ^2.0.0
   flutter_hooks: '>=0.18.2 <0.21.0'