Fix readme links

Author: alamb

datafusion/proto/README.md

@@ -26,4 +26,4 @@ when building a distributed query engine.
 See [API Docs] for details and examples.
 
 [datafusion]: https://arrow.apache.org/datafusion
-[api docs]: http://docs.rs/datafusion-substrait/latest/datafusion-substrait
+[api docs]: http://docs.rs/datafusion-proto/latest

datafusion/substrait/README.md

@@ -23,4 +23,4 @@ This crate contains a [Substrait] producer and consumer for Apache Arrow
 [DataFusion] plans. See [API Docs] for details and examples.
 
 [substrait]: https://substrait.io
-[api docs]: https://docs.rs/datafusion-substrait/latest/datafusion_substrait
+[api docs]: https://docs.rs/datafusion-substrait/latest