Merge branch 'develop' into release/4.2.0

packages/stream_chat_flutter/lib/src/attachment/attachment.dart

@@ -1,6 +1,5 @@
 export 'attachment_upload_state_builder.dart';
-export 'attachment_widget.dart'
-    show AttachmentError, AttachmentSource, AttachmentSourceX;
+export 'attachment_widget.dart' show AttachmentError, AttachmentSource;
 export 'file_attachment.dart';
 export 'giphy_attachment.dart';
 export 'image_attachment.dart';

packages/stream_chat_flutter/lib/src/attachment/attachment_widget.dart

@@ -7,14 +7,10 @@ enum AttachmentSource {
   local,
 
   /// Attachment is uploaded
-  network,
-}
+  network;
 
-/// Extension for identifying type of attachment
-extension AttachmentSourceX on AttachmentSource {
   /// The [when] method is the equivalent to pattern matching.
   /// Its prototype depends on the AttachmentSource defined.
-  // ignore: missing_return
   T when<T>({
     required T Function() local,
     required T Function() network,