Accessibility: After [35130], adjust the `h2.nav-tab-wrapper` selector to only override `.wrap > h2:first-child`.

This improves compatibility with plugins that use navigation tabs as a first H2 heading on their screens.

Props afercia.
Fixes #33559.

git-svn-id: https://develop.svn.wordpress.org/trunk@35496 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/css/common.css

@@ -2018,7 +2018,7 @@ html.wp-toolbar {
 }
 
 h1.nav-tab-wrapper, /* Back-compat for pre-4.4 */
-h2.nav-tab-wrapper,
+.wrap h2.nav-tab-wrapper, /* higher specificity to override .wrap > h2:first-child */
 h3.nav-tab-wrapper {
 	border-bottom: 1px solid #ccc;
 	margin: 0;