fix link

Author: mrijken

Cargo.toml

@@ -1,10 +1,10 @@
 [package]
 name = "unpoly"
-version = "0.2.0"
+version = "0.2.1"
 edition = "2021"
 license = "MIT"
 readme = "README.md"
-repository = "https://github.com/mrijken/unpoly-rs"
+repository = "https://github.com/mrijken/unpoly_rs"
 keywords = ["unpoly", "axum"]
 authors = ["Marc Rijken <marc@rijken.org>"]
 description = "Helper for the Unpoly API, initially for usage in Axum handlers"