Link to successor of deprecated avro-rs crate

Author: dtolnay

_src/README.md

@@ -81,7 +81,7 @@ Serde by the community.
 [Pickle]: https://github.com/birkenfeld/serde-pickle
 [RON]: https://github.com/ron-rs/ron
 [BSON]: https://github.com/mongodb/bson-rust
-[Avro]: https://github.com/flavray/avro-rs
+[Avro]: https://docs.rs/apache-avro
 [JSON5]: https://github.com/callum-oakley/json5-rs
 [URL]: https://docs.rs/serde_qs
 [Envy]: https://github.com/softprops/envy