Fix doc links to std::fmt `std::format` and `core::write` macros' docs linked to `core::fmt` for format string reference, even though only `std::fmt` has format string documentation (and the link titles were `std::fmt`)
Fix doc links to std::fmt `std::format` and `core::write` macros' docs linked to `core::fmt` for format string reference, even though only `std::fmt` has format string documentation (and the link titles were `std::fmt`)