refactor(lib): Import tracing macros per-module

Instead of one #[macro_use] at the crate root.

src/client/connect/http.rs

@@ -14,6 +14,7 @@ use http::uri::{Scheme, Uri};
 use pin_project_lite::pin_project;
 use tokio::net::{TcpSocket, TcpStream};
 use tokio::time::Sleep;
+use tracing::{debug, trace, warn};
 
 use super::dns::{self, resolve, GaiResolver, Resolve};
 use super::{Connected, Connection};