test: update WPT encoding tests

PR-URL: https://github.com/nodejs/node/pull/43958
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Feng Yu <F3n67u@outlook.com>
Reviewed-By: Darshan Sen <raisinten@gmail.com>

test/fixtures/wpt/encoding/sharedarraybuffer.https.html.headers

@@ -0,0 +1,2 @@
+Cross-Origin-Opener-Policy:same-origin
+Cross-Origin-Embedder-Policy:require-corp