Use clear-site-data header instead of setting empty cookie

functions/api/auth/session.ts

@@ -35,7 +35,7 @@ export async function onRequestDelete(context: RequestContext) {
 
     return new Response(null, {
       headers: {
-        "set-cookie": "_s=; Max-Age=0",
+        "clear-site-data": '"cookies"',
       },
       status: 204,
     });