(webhooks/sync-data) stringify the payload (#2026)

Author: alexisintech

docs/webhooks/sync-data.mdx

@@ -209,7 +209,7 @@ These steps apply to any Clerk event. To make the setup process easier, it's rec
           // If successful, the payload will be available from 'evt'
           // If verification fails, error out and return error code
           try {
-            evt = wh.verify(payload, {
+            evt = wh.verify(JSON.stringify(payload), {
               'svix-id': svix_id as string,
               'svix-timestamp': svix_timestamp as string,
               'svix-signature': svix_signature as string,