bump clippy crates to edition 2021

Cargo.toml

@@ -8,7 +8,7 @@ license = "MIT OR Apache-2.0"
 keywords = ["clippy", "lint", "plugin"]
 categories = ["development-tools", "development-tools::cargo-plugins"]
 build = "build.rs"
-edition = "2018"
+edition = "2021"
 publish = false
 
 [[bin]]

clippy_dev/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "clippy_dev"
 version = "0.0.1"
-edition = "2018"
+edition = "2021"
 
 [dependencies]
 bytecount = "0.6"

clippy_lints/Cargo.toml

@@ -6,7 +6,7 @@ repository = "https://github.com/rust-lang/rust-clippy"
 readme = "README.md"
 license = "MIT OR Apache-2.0"
 keywords = ["clippy", "lint", "plugin"]
-edition = "2018"
+edition = "2021"
 
 [dependencies]
 cargo_metadata = "0.12"

clippy_utils/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "clippy_utils"
 version = "0.1.57"
-edition = "2018"
+edition = "2021"
 publish = false
 
 [dependencies]