Update to Rust 2021.

Author: sunfishcode

Cargo.toml

@@ -6,7 +6,7 @@ description = "Set filesystem timestamps"
 documentation = "https://docs.rs/fs-set-times"
 license = "Apache-2.0 WITH LLVM-exception OR Apache-2.0 OR MIT"
 repository = "https://github.com/bytecodealliance/fs-set-times"
-edition = "2018"
+edition = "2021"
 keywords = ["api", "file"]
 categories = ["filesystem"]
 exclude = ["/.github"]

src/set_times.rs

@@ -1,17 +1,14 @@
 use crate::SystemTimeSpec;
 use io_lifetimes::AsFilelike;
+#[cfg(not(windows))]
+use rustix::{
+    fs::{futimens, utimensat, AtFlags, Timestamps, CWD},
+    fs::{UTIME_NOW, UTIME_OMIT},
+    time::Timespec,
+};
 use std::path::Path;
 use std::time::SystemTime;
 use std::{fs, io};
-#[cfg(not(windows))]
-use {
-    rustix::{
-        fs::{futimens, utimensat, AtFlags, Timestamps, CWD},
-        fs::{UTIME_NOW, UTIME_OMIT},
-        time::Timespec,
-    },
-    std::convert::TryInto,
-};
 #[cfg(windows)]
 use {
     std::{