Remove unused rustversion dependency of axum-core

Author: jplatte

Cargo.lock

@@ -42,7 +42,6 @@ http-body = "1.0.0"
 http-body-util = "0.1.0"
 mime = "0.3.16"
 pin-project-lite = "0.2.7"
-rustversion = "1.0.9"
 sync_wrapper = "1.0.0"
 tower-layer = "0.3"
 tower-service = "0.3"