Schema for WebRTCStats - 2023-07-20

[balazskreith]

Based on recent changes in webrtc stats, the following fields are missing from schema:

inbound-rtp:
pauseCount
totalPausesDuration
freezeCount
totalFreezesDuration
powerEfficientDecoder?:;
framesAssembledFromMultiplePackets?:;
totalAssemblyTime?:;
retransmittedPacketsReceived?:;
retransmittedBytesReceived?:;

outbound-rtp:
powerEfficientEncoding
scalabilityMode

ice-candidate-stats:
foundation?: string;
relatedAddress?: string;
relatedPort?: number;
userNameFragment?: string;
tcpType?: RtcIceTcpCandidateType;