Problem:
Related to #2764
s2n-quic-events currently makes some assumptions specific to the QUIC protocol, such as exposing the QUIC version in the publisher interface. To remove these assumptions without breaking the existing s2n-quic events systems, a new protocol mode option will be added to generate an events system in either a QUIC or TLS mode. s2n-tls will generate its events system with the new TLS mode, which will not contain these QUIC-specific assumptions.