Delete all autocargo project-level edition settings

Summary: The `edition` setting in `[defaults.package]` makes autocargo generate a Cargo.toml that is inconsistent with the Rust edition of the corresponding Buck target. This setting just should not exist. Project-level edition should be controlled using a PACKAGE file ({D72478333}).

Reviewed By: quark-zju

Differential Revision: D75799054

fbshipit-source-id: 87b6bd1d7bd92543be6651c150a71882dd165820

Author: David Tolnay

Cargo.toml

@@ -4,7 +4,7 @@
 name = "reindeer"
 version = "0.0.0"
 authors = ["Facebook"]
-edition = "2021"
+edition = "2024"
 repository = "https://github.com/facebookincubator/reindeer"
 license = "MIT"