tls_handshakes: add endpoint addresses to handshake list (#711)

* tls_handshakes: add IP addresses

* tls_handshakes: extract ip from tcp-connect

* tls_handshake: switched to trace event

* saver.go: get remoteAddr before handshake

Not sure whether this is strictly necessary, but I'd rather take the
remoteAddr before calling Handshake, just in case a future version
of the handshake closes the `conn`. In such a case, `conn.RemoteAddr`
would return `nil` and we would crash here.

This occurred to me while reading once again the diff before merging.

Co-authored-by: decfox <decfox>
Co-authored-by: Simone Basso <bassosimone@gmail.com>

internal/engine/netx/tlsdialer/saver.go

@@ -29,9 +29,11 @@ func (h SaverTLSHandshaker) Handshake(
 		TLSServerName: config.ServerName,
 		Time:          start,
 	})
+	remoteAddr := conn.RemoteAddr().String()
 	tlsconn, state, err := h.TLSHandshaker.Handshake(ctx, conn, config)
 	stop := time.Now()
 	h.Saver.Write(trace.Event{
+		Address:            remoteAddr,
 		Duration:           stop.Sub(start),
 		Err:                err,
 		Name:               "tls_handshake_done",