Fix a few notices

lib/ui/widgets/text_rich_content_widget.dart

@@ -19,7 +19,7 @@ class TextRichContentWidget extends StatelessWidget {
     this.text, {
     this.textAlign,
     this.style,
-  }) : assert(text != null);
+  });
 
   /// Parse the text and return it as a list of span elements
   static List<TextSpan> _parse(String text, TextStyle? style) {