doc: typo fixes (#3401)

tokio/src/io/blocking.rs

@@ -175,7 +175,7 @@ where
     }
 }
 
-/// Repeates operations that are interrupted
+/// Repeats operations that are interrupted
 macro_rules! uninterruptibly {
     ($e:expr) => {{
         loop {

tokio/src/runtime/mod.rs

@@ -10,7 +10,7 @@
 //!
 //! Tokio's [`Runtime`] bundles all of these services as a single type, allowing
 //! them to be started, shut down, and configured together. However, often it is
-//! not required to configure a [`Runtime`] manually, and user may just use the
+//! not required to configure a [`Runtime`] manually, and a user may just use the
 //! [`tokio::main`] attribute macro, which creates a [`Runtime`] under the hood.
 //!
 //! # Usage
@@ -114,7 +114,7 @@
 //!
 //! The multi-thread scheduler executes futures on a _thread pool_, using a
 //! work-stealing strategy. By default, it will start a worker thread for each
-//! CPU core available on the system. This tends to be the ideal configurations
+//! CPU core available on the system. This tends to be the ideal configuration
 //! for most applications. The multi-thread scheduler requires the `rt-multi-thread`
 //! feature flag, and is selected by default:
 //! ```