relay: Stop advertising HSv2 protocol version
We just disabled v2 in 035+ and so we should make the relays stop advertising the protocol version.
Tor clients don't us protocol versions to learn if a relay can be used for onion service v2 so this shouldn't change much. But it could for any alt-implementation out there that uses those for v2.
Essentially, relay protocol version should be set to:
3which is v2 specific.
1which is v2 specific.