fix(graphql): upgrade rxdart 0.28.0 (zino-hofmann#1454)

* chore(graphql): upgrade rxdart 0.28.0

* Update packages/graphql/pubspec.yaml

Co-authored-by: Rene Floor <rene.floor@ah.nl>

---------

Co-authored-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
Co-authored-by: Rene Floor <rene.floor@ah.nl>

Author: 3 people

packages/graphql/pubspec.yaml

@@ -20,7 +20,7 @@ dependencies:
   collection: ^1.15.0
   web_socket_channel: '>=2.3.0 <=2.4.0'
   stream_channel: ^2.1.0
-  rxdart: ^0.27.1
+  rxdart: '>=0.27.1 <0.29.0'
   uuid: ^4.0.0
 
 dev_dependencies: