Mark MakeErasedHandler as unused for CI

axum/src/boxed.rs

@@ -68,6 +68,7 @@ pub(crate) trait ErasedIntoRoute<S, E>: Send {
     fn call_with_state(self: Box<Self>, request: Request, state: S) -> RouteFuture<E>;
 }
 
+#[allow(dead_code)]
 pub(crate) struct MakeErasedHandler<H, S> {
     pub(crate) handler: H,
     pub(crate) into_route: fn(H, S) -> Route,