rust: move to Rust 2024

I'd like to use let chains.

Probably this isn't necessary to do for every crate, but I don't feel
like maintaining a mismash.

crates/regex/Cargo.toml

@@ -11,7 +11,7 @@ repository = "https://github.com/BurntSushi/ripgrep/tree/master/crates/regex"
 readme = "README.md"
 keywords = ["regex", "grep", "search", "pattern", "line"]
 license = "Unlicense OR MIT"
-edition = "2021"
+edition = "2024"
 
 [dependencies]
 bstr = "1.6.2"

crates/regex/src/ban.rs

@@ -9,7 +9,7 @@ pub(crate) fn check(expr: &Hir, byte: u8) -> Result<(), Error> {
     assert!(byte.is_ascii(), "ban byte must be ASCII");
     let ch = char::from(byte);
     let invalid = || Err(Error::new(ErrorKind::Banned(byte)));
-    match expr.kind() {
+    match *expr.kind() {
         HirKind::Empty => {}
         HirKind::Literal(hir::Literal(ref lit)) => {
             if lit.iter().find(|&&b| b == byte).is_some() {