Disable Failing Webhooks (#11966)

* todo comment

* add failures field to webhooks and sanitize

* implement logic

* use update instead of save

* specify timeout and maximum number of retries

* add tests

website/server/controllers/api-v3/webhook.js

@@ -108,7 +108,7 @@ api.addWebhook = {
   url: '/user/webhook',
   async handler (req, res) {
     const { user } = res.locals;
-    const webhook = new Webhook(req.body);
+    const webhook = new Webhook(Webhook.sanitize(req.body));
 
     const existingWebhook = user.webhooks.find(hook => hook.id === webhook.id);