fix deprecation warning error when inspecting server hostname

[dati18]

LocalSettings.php detects whether the current request is coming from a local dev env by inspecting the server hostname. I added isset($_SERVER['SERVER_NAME']) so preg_match() method is called only when the variable exists. This helps remove these type of errors in the logs:

Warning: Undefined array key "SERVER_NAME" in /var/www/html/w/wbstack/src/Settings/LocalSettings.php on line 27
Deprecated: preg_match(): Passing null to parameter #2 ($subject) of type string is deprecated in /var/www/html/w/wbstack/src/Settings/LocalSettings.php on line 27

[tarrow]

Generally looks good to me! Looks like the deprecation warning comes from preg_match.

I didn't test locally but given the automated smoke tests work I'm happy. Let's ship this to staging sooner than later though just in case it blows up

[outdooracorn]

Let's goooo! 🚀