doc: fix the inline code-block at the NodeDhKeyGenParams class

PR-URL: #40341
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Zijian Liu <lxxyxzj@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Gerhard Stöbich <deb2001-github@yahoo.de>
Reviewed-By: Qingyu Deng <i@ayase-lab.com>

doc/api/webcrypto.md

@@ -1511,7 +1511,7 @@ added: v15.0.0
 
 * Type: {string} Must be `'NODE-DH'`.
 
-#### Class: NodeDhKeyGenParams`
+#### Class: `NodeDhKeyGenParams`
 <!-- YAML
 added: v15.0.0
 -->