src: fix compiler warnings in node_crypto.cc

During the time between https://github.com/nodejs/node/pull/24234
being opened and it landing, a V8 update occurred that deprecated
several APIs. This commit fixes the following compiler warnings:

../src/node_crypto.cc:3342:11:
  warning: 'Set' is deprecated: Use maybe version

../src/node_crypto.cc:3345:13:
  warning: 'GetFunction' is deprecated: Use maybe version

PR-URL: https://github.com/nodejs/node/pull/25205


Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>