fix mismatch between title and toc for F.22

CppCoreGuidelines.md

@@ -2236,7 +2236,7 @@ Parameter passing expression rules:
 
 Parameter passing semantic rules:
 
-* [F.22: Use `T*` or `owner<T*>` or a smart pointer to designate a single object](#Rf-ptr)
+* [F.22: Use `T*` or `owner<T*>` to designate a single object](#Rf-ptr)
 * [F.23: Use a `not_null<T>` to indicate "null" is not a valid value](#Rf-nullptr)
 * [F.24: Use a `span<T>` or a `span_p<T>` to designate a half-open sequence](#Rf-range)
 * [F.25: Use a `zstring` or a `not_null<zstring>` to designate a C-style string](#Rf-zstring)