Handle HTTP/3 SETTINGS on 0-RTT client connection. In IETF QUIC, if 0-RTT is enabled, the client will receive 2 SETTINGS, one from cache and one from the fresh server sent SETTINGS. If 0-RTT is accepted, the server shouldn't change dynamic table capacity according to https://quicwg.org/base-drafts/draft-ietf-quic-qpack.html#name-maximum-dynamic-table-capac. For other settings, https://www.google.com/url?sa=D&q=https%3A%2F%2Fquicwg.org%2Fbase-drafts%2Fdraft-ietf-quic-http.html%23name-initialization specifies they shouldn't be decreased. When 0-RTT is rejected, our current approach is to retransmit 0-RTT packets. If the server changes SETTINGS, our implementation doesn't have an easy way to comply with the new SETTINGS, thus we close the connection too. Protected by quic_enable_zero_rtt_for_tls PiperOrigin-RevId: 316128955 Change-Id: I84b277b3c57d6a8009aec5a547c6416542122ec6