remove unused code

Signed-off-by: Yoshua Wuyts <[email protected]>

Author: yoshuawuyts

README.md

@@ -11,8 +11,6 @@ Experimental language-level polyfills for Async Rust.
 ## Examples
 
 ```rust
-use async_std::task;
-
 #[async_attributes::main]
 async fn main() {
     println!("Hello, world!");

src/lib.rs

@@ -3,8 +3,6 @@
 //! # Examples
 //!
 //! ```
-//! use async_std::task;
-//!
 //! #[async_attributes::main]
 //! async fn main() {
 //!     println!("Hello, world!");