chore: disable cast_nullable_to_non_nullable rule

Author: dkrutskikh

analysis_options.yaml

@@ -72,7 +72,7 @@ linter:
     - camel_case_types
     - cancel_subscriptions
     - cascade_invocations
-    - cast_nullable_to_non_nullable
+    #    - cast_nullable_to_non_nullable
     - close_sinks
     - comment_references
     - constant_identifier_names

test/analyzers/lint_analyzer/rules/rules_list/avoid_returning_widgets/avoid_returning_widgets_test.dart

@@ -95,7 +95,7 @@ void main() {
           '@swidget\n'
               'Widget _getStatelessFunctionalWidget() => Container();',
           '@hwidget\n'
-              'Widget _getHookFunctionalWidget() => Container();'
+              'Widget _getHookFunctionalWidget() => Container();',
         ],
         messages: [
           'Avoid returning widgets from a function.',