sync: add doc aliases for blocking_* methods (#5448)

tokio/src/sync/mpsc/bounded.rs

@@ -326,6 +326,7 @@ impl<T> Receiver<T> {
     /// ```
     #[track_caller]
     #[cfg(feature = "sync")]
+    #[cfg_attr(docsrs, doc(alias = "recv_blocking"))]
     pub fn blocking_recv(&mut self) -> Option<T> {
         crate::future::block_on(self.recv())
     }
@@ -696,6 +697,7 @@ impl<T> Sender<T> {
     /// ```
     #[track_caller]
     #[cfg(feature = "sync")]
+    #[cfg_attr(docsrs, doc(alias = "send_blocking"))]
     pub fn blocking_send(&self, value: T) -> Result<(), SendError<T>> {
         crate::future::block_on(self.send(value))
     }

tokio/src/sync/mpsc/unbounded.rs

@@ -243,6 +243,7 @@ impl<T> UnboundedReceiver<T> {
     /// ```
     #[track_caller]
     #[cfg(feature = "sync")]
+    #[cfg_attr(docsrs, doc(alias = "recv_blocking"))]
     pub fn blocking_recv(&mut self) -> Option<T> {
         crate::future::block_on(self.recv())
     }

tokio/src/sync/mutex.rs

@@ -417,6 +417,7 @@ impl<T: ?Sized> Mutex<T> {
     /// ```
     #[track_caller]
     #[cfg(feature = "sync")]
+    #[cfg_attr(docsrs, doc(alias = "lock_blocking"))]
     pub fn blocking_lock(&self) -> MutexGuard<'_, T> {
         crate::future::block_on(self.lock())
     }

tokio/src/sync/oneshot.rs

@@ -1056,6 +1056,7 @@ impl<T> Receiver<T> {
     /// ```
     #[track_caller]
     #[cfg(feature = "sync")]
+    #[cfg_attr(docsrs, doc(alias = "recv_blocking"))]
     pub fn blocking_recv(self) -> Result<T, RecvError> {
         crate::future::block_on(self)
     }