Bug 1628418 - ARIA reflection: update wpt test expectation r=MarcoZ

Depends on D71772

Differential Revision: https://phabricator.services.mozilla.com/D71970

testing/web-platform/meta/dom/nodes/aria-attribute-reflection.tentative.html.ini

@@ -1,5 +1,2 @@
 [aria-attribute-reflection.tentative.html]
   prefs: [accessibility.ARIAReflection.enabled:true]
-  [aria-selected attribute reflects.]
-    expected: FAIL
-