Evaluate ConnectionTracingKey as connection tracking

[everesio]

quic-go/quic-go in the v0.45.0 provides a breaking change regarding ConnectionTracingKey. Evaluate it as a possibility for connection tracking.

Breaking Changes

• Connection.NextConnection now takes a context and correctly handles handshake failures (#4551)

• qlog: DefaultTracer was renamed to DefaultConnectionTracer (#4556)

• The ConnectionTracingKey is now deprecated. Use Transport.ConnContext to set your own tracing key (#4532)