Coding Standards: Remove unreachable break statement after exit in switch.

This resolves static analysis warnings about an unreachable statement. 

Developed in #8956

Follow-up to [41131].

Props justlevine, johnbillion.
See #64238.


git-svn-id: https://develop.svn.wordpress.org/trunk@61303 602fd350-edb4-49c9-b593-d223f7449a82

Author: westonruter

src/wp-admin/network/sites.php

@@ -240,7 +240,7 @@
 								<?php
 								require_once ABSPATH . 'wp-admin/admin-footer.php';
 								exit;
-							break;
+							// By exiting, there's no longer a switch to break out of.
 
 							case 'spam':
 							case 'notspam':