fix(webhook_listeners): Avoid collision between two identical calls at the same second

The job list needs argument to be unique for each registered job, so add
 a random string on top of time to make sure the same call can be
 registered several times at the same second.

Signed-off-by: Côme Chilliet <come.chilliet@nextcloud.com>

apps/webhook_listeners/lib/Listener/WebhooksEventListener.php

@@ -50,6 +50,8 @@ class WebhooksEventListener implements IEventListener {
 					[
 						$data,
 						$webhookListener->getId(),
+						/* Random string to avoid collision with another job with the same parameters */
+						bin2hex(random_bytes(5)),
 					]
 				);
 			}