Move QuicIetfTransportErrorCodes, QuicErrorCodeToIetfMapping, and QuicErrorCodeToTransportErrorCode from quic_types to quic_error_codes, next to closely related QuicHttp3ErrorCode. gfe-relnote: Refactor, no functional change, not protected. PiperOrigin-RevId: 305731890 Change-Id: Ibded7eedf8fb05b3fedbe13083715a7c9aded038