re-export rt in web and add main macro (#1575)

src/types/json.rs

@@ -319,6 +319,7 @@ where
     U: DeserializeOwned + 'static,
 {
     /// Create `JsonBody` for request.
+    #[allow(clippy::borrow_interior_mutable_const)]
     pub fn new(
         req: &HttpRequest,
         payload: &mut Payload,