chore: set min flutter version to '>1.20.0' in packages where set to … (#757)

Author: Travis Sheppard

packages/amplify_analytics_pinpoint/pubspec.yaml

@@ -4,8 +4,8 @@ version: 0.2.1
 homepage: https://github.com/aws-amplify/amplify-flutter/tree/main/packages/amplify_analytics_pinpoint
 
 environment:
-  sdk: '>=2.12.0 <3.0.0'
-  flutter: ^1.20.0
+  sdk: ">=2.12.0 <3.0.0"
+  flutter: ">=1.20.0"
 
 dependencies:
   flutter:

packages/amplify_api/pubspec.yaml

@@ -5,7 +5,7 @@ homepage: https://github.com/aws-amplify/amplify-flutter/tree/main/packages/ampl
 
 environment:
   sdk: ">=2.12.0 <3.0.0"
-  flutter: ^1.20.0
+  flutter: ">=1.20.0"
 
 dependencies:
   flutter:

packages/amplify_auth_cognito/example/pubspec.yaml

@@ -7,7 +7,7 @@ publish_to: "none" # Remove this line if you wish to publish to pub.dev
 
 environment:
   sdk: ">=2.12.0 <3.0.0"
-  flutter: ">=1.17.0 <2.0.0"
+  flutter: ">=2.2.0"
 
 dependencies:
   flutter:
@@ -36,10 +36,6 @@ dev_dependencies:
 # For information on the generic Dart part of this file, see the
 # following page: https://dart.dev/tools/pub/pubspec
 
-# Needed to avoid conflict for integration tests until flutter driver has null safe version of crypto https://github.com/flutter/flutter/issues/77282
-dependency_overrides:
-  crypto: ^3.0.0
-
 # The following section is specific to Flutter.
 flutter:
   # The following line ensures that the Material Icons font is

packages/amplify_datastore/pubspec.yaml

@@ -5,7 +5,7 @@ homepage: https://github.com/aws-amplify/amplify-flutter/tree/main/packages/ampl
 
 environment:
   sdk: ">=2.12.0 <3.0.0"
-  flutter: ">=1.17.0"
+  flutter: ">=1.20.0"
 
 dependencies:
   flutter:

packages/amplify_storage_s3/pubspec.yaml

@@ -4,8 +4,8 @@ version: 0.2.1
 homepage: https://github.com/aws-amplify/amplify-flutter/tree/main/packages/amplify_storage_s3
 
 environment:
-  sdk: '>=2.12.0 <3.0.0'
-  flutter: ^1.10.0
+  sdk: ">=2.12.0 <3.0.0"
+  flutter: ">=1.20.0"
 
 dependencies:
   flutter: