Fix trivial deprecations

Fix trivial deprecations

We should use SecTrustCopyCertificateChain and then access the CFArray instead of using the deprecated SecTrustGetCertificateCount

Use xpc_connection_send_message_with_reply_sync instead of xpc_connection_send_message_with_reply.

This also gives us the added benefit of not risking priority inversion, since xpc_connection_send_message_with_reply_sync takes care of that already.

Finally, use RtlGetVersion instead of deprecated GetVersionExA.