pre-fill the timezone

Signed-off-by: Simon L <szaimen@e.mail.de>

php/public/timezone.js

@@ -0,0 +1,7 @@
+document.addEventListener("DOMContentLoaded", function(event) {
+    // timezone
+    let timezone = document.getElementById("timezone");
+    if (timezone) {
+        timezone.value = Intl.DateTimeFormat().resolvedOptions().timeZone
+    }
+});