interfaces: reload GUI in the background

Take our chances with SSH.  It looks like using 'early'
facility surfaced this problem that was not as trigger
happy before.  The administration page does the same.

PR: https://forum.opnsense.org/index.php?topic=43995.0

src/www/interfaces.php

@@ -562,7 +562,7 @@ if ($_SERVER['REQUEST_METHOD'] === 'GET') {
 
                 system_routing_configure(false, array_keys($toapplylist));
                 filter_configure();
-                plugins_configure('early'); /* ensure GUI and SSH access */
+                configd_run('webgui restart 3', true);
             }
 
             clear_subsystem_dirty('interfaces');