feat(s2n-quic-dc): update MTU on dc path when MTU is updated #4896

Job	Run time
env	5s
s2n-quic-qns (debug)	2m 47s
s2n-quic-qns (release)	7m 10s
perf (s2n-quic, s2n-quic)	1m 8s
perf (s2n-quic-null, s2n-quic-null)	50s
attack (udp)	5m 25s
bench	18m 59s
interop (aioquic, s2n-quic)	16m 23s
interop (chrome, s2n-quic)	5m 22s
h3spec (s2n-tls)	14s
interop (go-x-net, s2n-quic)	12m 5s
h3spec (rustls)	13s
interop (kwik, s2n-quic)	13m 42s
interop (lsquic, s2n-quic)	12m 53s
interop (msquic, s2n-quic)	16m 39s
interop (mvfst, s2n-quic)	11m 25s
interop (neqo, s2n-quic)	15m 22s
interop (ngtcp2, s2n-quic)	14m 24s
interop (picoquic, s2n-quic)	16m 1s
interop (quic-go, s2n-quic)	12m 59s
interop (quiche, s2n-quic)	14m 26s
interop (quinn, s2n-quic)	13m 24s
interop (s2n-quic, aioquic)	13m 38s
interop (s2n-quic, go-x-net)	11m 45s
interop (s2n-quic, haproxy)	12m 0s
interop (s2n-quic, kwik)	12m 11s
interop (s2n-quic, lsquic)	11m 20s
interop (s2n-quic, msquic)	11m 36s
interop (s2n-quic, mvfst)	14m 45s
interop (s2n-quic, neqo)	12m 42s
interop (s2n-quic, nginx)	10m 36s
interop (s2n-quic, ngtcp2)	13m 7s
interop (s2n-quic, picoquic)	12m 0s
interop (s2n-quic, quic-go)	15m 17s
interop (s2n-quic, quiche)	11m 31s
interop (s2n-quic, quinn)	12m 19s
interop (s2n-quic, s2n-quic)	12m 31s
interop (s2n-quic, s2n-quic-rustls)	12m 29s
interop (s2n-quic, xquic)	12m 3s
interop (s2n-quic-rustls, s2n-quic)	12m 51s
interop (xquic, s2n-quic)	15m 18s
perf-report	9s
interop-report	15s
	7h 32m 19s

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