mark task::ready as unstable

Signed-off-by: Yoshua Wuyts <yoshuawuyts@gmail.com>

Author: yoshuawuyts

src/task/mod.rs

@@ -24,6 +24,8 @@
 #[doc(inline)]
 pub use std::task::{Context, Poll, Waker};
 
+#[cfg(feature = "unstable")]
+#[cfg_attr(feature = "docs", doc(cfg(unstable)))]
 #[doc(inline)]
 pub use async_macros::ready;