fix: fixed onShowMessage not showing up for some aspects

lib/src/giphy_attachment.dart

@@ -330,6 +330,7 @@ class GiphyAttachment extends StatelessWidget {
                 userName: message.user.name,
                 sentAt: message.createdAt,
                 message: message,
+                onShowMessage: onShowMessage,
               ),
             );
           }));

lib/src/image_group.dart

@@ -10,11 +10,13 @@ class ImageGroup extends StatelessWidget {
     @required this.images,
     @required this.message,
     @required this.size,
+    this.onShowMessage,
   }) : super(key: key);
 
   final List<Attachment> images;
   final Message message;
   final Size size;
+  final ShowMessageCallback onShowMessage;
 
   @override
   Widget build(BuildContext context) {
@@ -119,6 +121,7 @@ class ImageGroup extends StatelessWidget {
             userName: message.user.name,
             sentAt: message.createdAt,
             message: message,
+            onShowMessage: onShowMessage,
           ),
         ),
       ),

lib/src/message_widget.dart

@@ -736,6 +736,7 @@ class _MessageWidgetState extends State<MessageWidget> {
               ),
               images: images,
               message: widget.message,
+              onShowMessage: widget.onShowMessage,
             ),
           ),
         ),