Update Webhook.php

Fix deprecated warning in php 8.1

`Deprecated: filter_var(): Passing null to parameter #3 ($options) of type array|int is deprecated in /usr/local/var/www/mytiki.life-basic-upgrade/vendor/phpbu/phpbu/src/Log/Webhook.php on line 137`

Author: leevigraham

src/Log/Webhook.php

@@ -132,7 +132,7 @@ public function setup(array $options)
         // PHP >7.2 deprecated the filter options and enabled them by default
         $filterOptions = version_compare(PHP_VERSION, '7.2.0', '<')
                        ? FILTER_FLAG_SCHEME_REQUIRED | FILTER_FLAG_HOST_REQUIRED
-                       : null;
+                       : 0;
 
         if (!filter_var($options['uri'], FILTER_VALIDATE_URL, $filterOptions)) {
             throw new Exception('webhook URI is invalid');