Function join_group_call 

pub async fn join_group_call(
    group_call_id: i32,
    participant_id: Option<MessageSender>,
    audio_source_id: i32,
    payload: String,
    is_muted: bool,
    is_my_video_enabled: bool,
    invite_hash: String,
    client_id: i32,
) -> Result<Text, Error>

Joins an active group call. Returns join response payload for tgcalls

Arguments

• group_call_id - Group call identifier
• participant_id - Identifier of a group call participant, which will be used to join the call; pass null to join as self; video chats only
• audio_source_id - Caller audio channel synchronization source identifier; received from tgcalls
• payload - Group call join payload; received from tgcalls
• is_muted - Pass true to join the call with muted microphone
• is_my_video_enabled - Pass true if the user’s video is enabled
• invite_hash - If non-empty, invite hash to be used to join the group call without being muted by administrators
• client_id - The client id to send the request to