Administration: Fix focus outline being cut off for the metabox collapse and move buttons.

Fixes an issue where the focus outline on metabox collapse buttons and move handles was being clipped.

Props abcd95, audrasjb, brianhogg, darshitrajyaguru97, poena, wildworks.
Fixes #65060.

git-svn-id: https://develop.svn.wordpress.org/trunk@62232 602fd350-edb4-49c9-b593-d223f7449a82

Author: t-hamano

src/wp-admin/css/common.css

@@ -3340,7 +3340,7 @@ img {
 .postbox .handle-order-higher:focus,
 .postbox .handle-order-lower:focus,
 .postbox .handlediv:focus {
-	box-shadow: 0 0 0 var(--wp-admin-border-width-focus, 1.5px) var(--wp-admin-theme-color);
+	box-shadow: inset 0 0 0 var(--wp-admin-border-width-focus, 1.5px) var(--wp-admin-theme-color);
 	border-radius: 50%;
 	/* Only visible in Windows High Contrast mode */
 	outline: 2px solid transparent;