Suppress admin notices on the about page.

Brings back [19393], accidentally reverted in [26718].

props ocean90.
fixes #26519.


git-svn-id: https://develop.svn.wordpress.org/trunk@26847 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/css/wp-admin.css

@@ -7848,6 +7848,11 @@ body.press-this {
 	font-size: 15px;
 }
 
+.about-wrap div.updated,
+.about-wrap div.error {
+	display: none !important;
+}
+
 .about-wrap hr {
 	border: 0;
 	height: 0;