[Gardening]: NEW TEST ( Sonoma? ): [ Sonoma wk2 ] fast/scrolling/mac/…

…scrollbars/very-wide-overlay-scrollbar.html is a flaky with timeouts and image diff

https://bugs.webkit.org/show_bug.cgi?id=264306
rdar://118028009

Unreviewed test gardening.

Adding test expectation

* LayoutTests/platform/mac-wk2/TestExpectations:

Canonical link: https://commits.webkit.org/270303@main

LayoutTests/platform/mac-wk2/TestExpectations

@@ -1987,3 +1987,5 @@ http/tests/webgpu/webgpu/api/operation/render_pipeline/primitive_topology.html [
 webkit.org/b/263920 svg/transforms/transformed-text-fill-gradient.html [ Pass ImageOnlyFailure ]
 
 webkit.org/b/264266 [ Ventura+ x86_64 ] imported/w3c/web-platform-tests/css/filter-effects/filters-drop-shadow-002.html [ ImageOnlyFailure ]
+
+webkit.org/b/264306 [ Sonoma+ ] fast/scrolling/mac/scrollbars/very-wide-overlay-scrollbar.html [ Pass ImageOnlyFailure Timeout ]