copyWith method 
    
    
    
  Implementation
  JoinGroupCall copyWith({
  int? groupCallId,
  MessageSender? participantId,
  int? audioSourceId,
  String? payload,
  bool? isMuted,
  bool? isMyVideoEnabled,
  String? inviteHash,
}) => JoinGroupCall(
  groupCallId: groupCallId ?? this.groupCallId,
  participantId: participantId ?? this.participantId,
  audioSourceId: audioSourceId ?? this.audioSourceId,
  payload: payload ?? this.payload,
  isMuted: isMuted ?? this.isMuted,
  isMyVideoEnabled: isMyVideoEnabled ?? this.isMyVideoEnabled,
  inviteHash: inviteHash ?? this.inviteHash,
);