Update default timezone value

In case the ENV timezone value is missing, which should never happen as it is a require .env variable

Author: pH-7

app/settings.php

@@ -7,7 +7,7 @@
 ini_set('display_errors', IS_DEBUG_MODE);
 
 // Timezone
-date_default_timezone_set($_ENV['TIMEZONE'] ?? 'Europe/Dublin');
+date_default_timezone_set($_ENV['TIMEZONE'] ?? 'Europe/London');
 
 // Settings
 $settings = [];