test: fix typo in test-http2-invalidheaderfield.js

Psuedo -> Pseudo

PR-URL: #39021
Reviewed-By: Darshan Sen <raisinten@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: eltociear

test/parallel/test-http2-invalidheaderfield.js

@@ -4,7 +4,7 @@ if (!common.hasCrypto) { common.skip('missing crypto'); }
 
 // Check for:
 // Spaced headers
-// Psuedo headers
+// Pseudo headers
 // Capitalized headers
 
 const http2 = require('http2');