Fix typo

Author: joshtriplett

src/breaking-changes/prelude.md

@@ -15,7 +15,7 @@ For this reason, [`TryFrom` and `TryInto`](https://github.com/rust-lang/rust/iss
 Unlike other item types, rustc's name resolution for macros does not support giving prelude macros a lower priority than other macros, even if the macro is unstable.
 As a general rule, avoid adding macros to the prelude except at edition boundaries.
 
-This issues was encoutered when trying to land the [`assert_matches!` macro](https://github.com/rust-lang/rust/issues/82913).
+This issue was encountered when trying to land the [`assert_matches!` macro](https://github.com/rust-lang/rust/issues/82913).
 
 ## Types