Administration: Add delete_count to wp_removable_query_args().

It's a single-use URL parameter that does not need to be passed to canonical URLs in the admin.

Props opurockey.
Fixes #50464.

git-svn-id: https://develop.svn.wordpress.org/trunk@48319 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/functions.php

@@ -1183,6 +1183,7 @@ function wp_removable_query_args() {
 		'activated',
 		'approved',
 		'deactivate',
+		'delete_count',
 		'deleted',
 		'disabled',
 		'doing_wp_cron',