cloudflare-worker: remove useless assignment to message variable

Signed-off-by: Josef Schlehofer <pepe.schlehofer@gmail.com>

Author: BKPepe

cloudflare-worker/src/index.js

@@ -699,7 +699,7 @@ export default {
       console.error("Webhook processing failed:", rawError);
 
       let name = "Error";
-      let message = "An unexpected error occurred";
+      let message;
 
       if (rawError instanceof Error) {
         name = rawError.name;