expand no permissions message

lib/widgets/composer/composer.dart

@@ -165,12 +165,14 @@ class Composer extends HookConsumerWidget {
                         ),
                       ]
                     : [
-                        Padding(
+                        Expanded(
+                          child: Padding(
                             padding: EdgeInsetsGeometry.all(8),
                             child: Text(
                               "You don't have permission to send messages in this room...",
                             ),
                           ),
+                        ),
                       ],
               ),
             ),