Fix url_launcher version constraint for Dart

Author: DataSab

pubspec.yaml

@@ -35,7 +35,7 @@ dependencies:
   shared_preferences: ^2.3.2
   intl: ^0.20.2
   easy_localization: ^3.0.3
-  url_launcher: ^6.3.2
+  url_launcher: ^6.2.6
   permission_handler: ^12.0.1
   country_picker: ^2.0.27
   advanced_search: ^2.2.6+1