Function assemble_state_events 

async fn assemble_state_events(
    services: &Services,
    state_events: Vec<PduEvent>,
    sender_user: &UserId,
    encrypted: bool,
    include_in_state: impl Fn(&PduEvent) -> bool + Send + Sync,
    event_fields: Option<&[String]>,
) -> Vec<Raw<AnySyncStateEvent>>