fix a spec test

Author: bartlomieju

tests/specs/run/require_esm/main.out

@@ -1,4 +1,6 @@
 [Module: null prototype] { sync_js: 1 }
 [Module: null prototype] { sync_mjs: 1 }
 error: Uncaught (in promise) Error: Top-level await is not allowed in synchronous evaluation
+require("./async.js");
+^
     at [WILDCARD]