fix: test ntfy without custom headers (#456)

endpoints/notifications/testntfynotifications.php

@@ -26,6 +26,9 @@ if ($_SERVER["REQUEST_METHOD"] === "POST") {
         $host = rtrim($data["host"], '/');
         $topic = $data["topic"];
         $headers = json_decode($data["headers"], true);
+        if ($headers === null) {
+            $headers = [];
+        }
         $customheaders = array_map(function ($key, $value) {
             return "$key: $value";
         }, array_keys($headers), $headers);

includes/version.php

@@ -1,3 +1,3 @@
 <?php
-$version = "v2.19.1";
+$version = "v2.19.2";
 ?>