Correct anchor

Author: harryhanYuhao

src/doc/rustdoc/src/what-is-rustdoc.md

@@ -35,7 +35,7 @@ a web browser, you will see a page with a search bar, and "Crate lib" at the
 top, with no contents.
 
 You can also use `cargo doc` to generate documentation for the whole project.
-See [Using rustdoc with Cargo](#rustdoc-cargo).
+See [Using rustdoc with Cargo](#using-rustdoc-with-cargo).
 
 ## Configuring rustdoc