Add `delete_count` to `wp_removable_query_args()`

[ocean90]

delete_count is set in the redirect URL after a user has been deleted. It's only used once to print the success message on wp-admin/users.php together with update argument which is already part of wp_removable_query_args().

[arpitgshah]

Do we need to set message for one time only whenever multiple users are going to remove from the list of the users page?

Can you please explain more about the issues?

[opurockey]

Apply patch

[ocean90]

In 48319:

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.