Update compiler/rustc_middle/src/ty/sty.rs

Co-authored-by: Nicholas Nethercote <[email protected]>

Author: lcnr

compiler/rustc_middle/src/ty/sty.rs

@@ -836,7 +836,7 @@ impl<'tcx> Ty<'tcx> {
         coroutine_args: GenericArgsRef<'tcx>,
     ) -> Ty<'tcx> {
         tcx.debug_assert_args_compatible(def_id, coroutine_args);
-        // HACK: Coroutine witnesse types are lifetime erased, so they
+        // HACK: Coroutine witness types are lifetime erased, so they
         // never reference any lifetime args from the coroutine. We erase
         // the regions here since we may get into situations where a
         // coroutine is recursively contained within itself, leading to