Revert "esm: remove experimental status from JSON modules"

This reverts commit ec8776da6fa77628e12718bb38cee687303d4137.

PR-URL: https://github.com/nodejs/node/pull/29754


Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Myles Borins <myles.borins@gmail.com>