Updated config/logging.php (#5179)

This adds a default emergency logger path to the logging config file.
This change goes hand-in-hand with my changes found here:
7a03776bc8

config/logging.php

@@ -95,6 +95,10 @@
             'driver' => 'monolog',
             'handler' => NullHandler::class,
         ],
+
+        'emergency' => [
+            'path' => storage_path('logs/laravel.log'),
+        ],
     ],
 
 ];