Use :focus-visible for focus rings in the styles tab

Bug: 396311936
Change-Id: I385b4519bc941e50b9e29c6e1ee72d791245d429
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/6695002
Reviewed-by: Ergün Erdoğmuş <[email protected]>
Commit-Queue: Philip Pfaffe <[email protected]>
Auto-Submit: Philip Pfaffe <[email protected]>

Author: pfaffe

front_end/panels/elements/stylePropertiesTreeOutline.css

@@ -255,7 +255,7 @@ devtools-icon.icon-link {
     margin-left: 16px;
   }
 
-  :focus {
+  :focus-visible {
     border-radius: var(--sys-size-2);
     outline: var(--sys-size-2) solid var(--sys-color-state-focus-ring);
   }