fix spawn function documentation
@@ -52,7 +52,7 @@ doc_rt_core! {
///
/// # Using `!Send` values from a task
///
- /// The task supplied to `spawn` must implement `!Send`. However, it is
+ /// The task supplied to `spawn` must implement `Send`. However, it is
/// possible to **use** `!Send` values from the task as long as they only
/// exist between calls to `.await`.
///
