Auto merge of rust-lang#5748 - carols10cents:tiny-docs-fix, r=flip1995

Change a noun to a verb to make the sentence complete

changelog: Fixed some grammar in the documentation for `await_holding_lock`.

Just a tiny little thing I found while using clippy <3

clippy_lints/src/await_holding_lock.rs

@@ -11,7 +11,7 @@ declare_clippy_lint! {
     /// non-async-aware MutexGuard.
     ///
     /// **Why is this bad?** The Mutex types found in syd::sync and parking_lot
-    /// are not designed to operator in an async context across await points.
+    /// are not designed to operate in an async context across await points.
     ///
     /// There are two potential solutions. One is to use an asynx-aware Mutex
     /// type. Many asynchronous foundation crates provide such a Mutex type. The