Fix master CI: PlayableActionSheet test overflows on stricter Flutter (#177)

Author: phanan

test/ui/screens/playable_action_sheet_test.dart

@@ -5,6 +5,7 @@ import 'package:app/providers/download_provider.dart';
 import 'package:app/providers/favorite_provider.dart';
 import 'package:app/ui/screens/playable_action_sheet.dart';
 import 'package:audio_service/audio_service.dart';
+import 'package:flutter/material.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:mockito/annotations.dart';
 import 'package:mockito/mockito.dart';
@@ -55,6 +56,10 @@ void main() {
         ],
         child: PlayableActionSheet(playable: song),
       ),
+      // The sheet is normally shown via showModalBottomSheet with
+      // isScrollControlled, which lets it overflow / scroll. When mounted
+      // bare, give it enough vertical room to lay out without overflow.
+      surfaceSize: const Size(414, 1024),
     );
   }