Fix broken links in the documentation (#1878)

.github/workflows/CI.yml

@@ -48,7 +48,7 @@ jobs:
     - uses: Swatinem/rust-cache@v1
     - name: cargo doc
       env:
-        RUSTDOCFLAGS: "-D broken-intra-doc-links"
+        RUSTDOCFLAGS: "-D rustdoc::all -A rustdoc::private-doc-tests"
       run: cargo doc --all-features --no-deps
 
   cargo-hack:

axum/src/docs/middleware.md

@@ -574,14 +574,14 @@ axum::Server::bind(&"0.0.0.0:3000".parse().unwrap())
 [`tower`]: https://crates.io/crates/tower
 [`tower-http`]: https://crates.io/crates/tower-http
 [tower-guides]: https://github.com/tower-rs/tower/tree/master/guides
-[`axum::middleware::from_fn`]: crate::middleware::from_fn
-[`middleware::from_fn`]: crate::middleware::from_fn
+[`axum::middleware::from_fn`]: fn@crate::middleware::from_fn
+[`middleware::from_fn`]: fn@crate::middleware::from_fn
 [tower-from-scratch-guide]: https://github.com/tower-rs/tower/blob/master/guides/building-a-middleware-from-scratch.md
 [`ServiceBuilder::map_request`]: tower::ServiceBuilder::map_request
 [`ServiceBuilder::map_response`]: tower::ServiceBuilder::map_response
 [`ServiceBuilder::then`]: tower::ServiceBuilder::then
 [`ServiceBuilder::and_then`]: tower::ServiceBuilder::and_then
-[`axum::middleware::from_extractor`]: crate::middleware::from_extractor
+[`axum::middleware::from_extractor`]: fn@crate::middleware::from_extractor
 [`Handler::layer`]: crate::handler::Handler::layer
 [`Router::layer`]: crate::routing::Router::layer
 [`MethodRouter::layer`]: crate::routing::MethodRouter::layer