typo

Author: BillWagner

docs/csharp/specification/toc.yml

@@ -184,7 +184,7 @@ items:
     - name: Lock object semantics
       href: ../../../_csharplang/proposals/lock-object.md
     - name: Allow `ref` and `unsafe`
-      href: ../../../_csharplang/proposals/ref-unsafe-in-terators-async.md 
+      href: ../../../_csharplang/proposals/ref-unsafe-in-iterators-async.md 
   - name: Namespaces
     items:
     - name: File scoped namespaces