Replace std::forward for clang-tidy

Should fix #4231
Could instead use:
<!std::is_copy_constructible_v<It>, It&, It>;

include/fmt/ranges.h

@@ -660,7 +660,9 @@ struct formatter<join_view<It, Sentinel, Char>, Char> {
   template <typename FormatContext>
   auto format(view_ref& value, FormatContext& ctx) const
       -> decltype(ctx.out()) {
-    auto it = std::forward<view_ref>(value).begin;
+    using iter =
+        conditional_t<std::is_rvalue_reference<view_ref>::value, It&, It>;
+    iter it = value.begin;
     auto out = ctx.out();
     if (it == value.end) return out;
     out = value_formatter_.format(*it, ctx);