doc: add missing YAML tag in esm.md

Refs: nodejs#41434

PR-URL: nodejs#41516
Reviewed-By: Richard Lau <[email protected]>
Reviewed-By: Darshan Sen <[email protected]>
Reviewed-By: Colin Ihrig <[email protected]>

Author: aduh95

doc/api/esm.md

@@ -591,7 +591,7 @@ would provide the exports interface for the instantiation of `module.wasm`.
 
 ## Top-level `await`
 
-<!--
+<!-- YAML
 added: v14.8.0
 -->