Remove on from API docs link

Author: stefanofusai

README.md

@@ -8,7 +8,7 @@ and offers both synchronous and asynchronous clients powered by [httpx](https://
 
 ## Documentation
 
-The REST API documentation can be found [on developers.cloudflare.com](https://developers.cloudflare.com/api). The full API of this library can be found in [api.md](api.md).
+The REST API documentation can be found on [developers.cloudflare.com](https://developers.cloudflare.com/api). The full API of this library can be found in [api.md](api.md).
 
 ## Installation