fix(s2n-quic-dc): handle possible secret control packet correctly #4735

Job	Run time
env	5s
s2n-quic-qns (debug)	2m 44s
s2n-quic-qns (release)	6m 56s
h3spec (s2n-tls)	14s
interop (aioquic, s2n-quic)	19m 50s
attack (udp)	5m 25s
bench	4m 10s
interop (chrome, s2n-quic)	5m 43s
h3spec (rustls)	15s
interop (go-x-net, s2n-quic)	11m 48s
interop (kwik, s2n-quic)	13m 51s
perf (s2n-quic, s2n-quic)	1m 11s
interop (lsquic, s2n-quic)	13m 2s
perf (s2n-quic-null, s2n-quic-null)	49s
interop (msquic, s2n-quic)	17m 11s
interop (mvfst, s2n-quic)	11m 44s
interop (neqo, s2n-quic)	14m 44s
interop (ngtcp2, s2n-quic)	14m 6s
interop (picoquic, s2n-quic)	17m 2s
interop (quic-go, s2n-quic)	12m 52s
interop (quiche, s2n-quic)	19m 26s
interop (quinn, s2n-quic)	12m 55s
interop (s2n-quic, aioquic)	15m 0s
interop (s2n-quic, go-x-net)	11m 16s
interop (s2n-quic, haproxy)	11m 15s
interop (s2n-quic, kwik)	12m 22s
interop (s2n-quic, lsquic)	11m 22s
interop (s2n-quic, msquic)	12m 37s
interop (s2n-quic, mvfst)	7m 15s
interop (s2n-quic, neqo)	12m 35s
interop (s2n-quic, nginx)	11m 32s
interop (s2n-quic, ngtcp2)	11m 57s
interop (s2n-quic, picoquic)	11m 51s
interop (s2n-quic, quic-go)	10m 18s
interop (s2n-quic, quiche)	10m 58s
interop (s2n-quic, quinn)	12m 0s
interop (s2n-quic, s2n-quic)	12m 40s
interop (s2n-quic, s2n-quic-rustls)	12m 36s
interop (s2n-quic, xquic)	11m 43s
interop (s2n-quic-rustls, s2n-quic)	15m 59s
interop (xquic, s2n-quic)	16m 49s
perf-report	11s
interop-report	16s
	7h 18m 35s

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