crypto: add crypto.diffieHellman

Currently, Node.js has separate (stateful) APIs for DH/ECDH, and no
support for ECDH-ES. This commit adds a single stateless function to
compute the DH/ECDH/ECDH-ES secret based on two KeyObjects.

PR-URL: https://github.com/nodejs/node/pull/31178


Reviewed-By: Sam Roberts <vieuxtech@gmail.com>