style: Change file view accent color to grey

Same as file chooser, we'll need this in case 47 ships without the new
grid.

src/resources/style.css

@@ -327,3 +327,10 @@ label.encrypted_zip {
 rubberband {
   border-radius: 6px;
 }
+
+.nautilus-list-view listview,
+.nautilus-grid-view gridview,
+.nautilus-network-view listview {
+  --accent-bg-color: #959595;
+  --accent-color: oklab(from var(--accent-bg-color) var(--standalone-color-oklab));
+}