Updating minor dependency and removing maximum dart version limit. (#62)

Author: yasirfolio3

pubspec.yaml

@@ -4,7 +4,7 @@ version: 1.0.1
 homepage: https://github.com/optimizely/optimizely-flutter-sdk
 
 environment:
-  sdk: ">=2.16.2 <3.0.0"
+  sdk: ">=2.16.2"
   flutter: ">=2.5.0"
 
 dependencies:
@@ -16,7 +16,7 @@ dev_dependencies:
     sdk: flutter
   flutter_test:
     sdk: flutter
-  flutter_lints: ^1.0.4
+  flutter_lints: ^2.0.1
   collection: ^1.16.0
 
 flutter: