Fix a few notices

lib/ui/routes/settings/custom_emojies_account_settings.dart

@@ -129,8 +129,7 @@ class _NewCustomEmojiDialog extends StatefulWidget {
   const _NewCustomEmojiDialog({
     Key? key,
     required this.currentList,
-  })  : assert(currentList != null),
-        super(key: key);
+  }) : super(key: key);
 
   @override
   _NewCustomEmojiDialogState createState() => _NewCustomEmojiDialogState();