use once_cell statement not needed

as macro uses fully qualified call

src/engine/mod.rs

@@ -56,7 +56,6 @@ use std::collections::BTreeMap;
 use std::sync::mpsc;
 use std::sync::mpsc::{Receiver, Sender};
 use std::thread;
-//use once_cell::sync::OnceCell; 
 
 use crate::Profile;
 //use async_trait::async_trait;