Migrate to rust 2021 edition

Author: marmeladema

Cargo.toml

@@ -2,7 +2,7 @@
 name = "sliceslice"
 version = "0.3.1"
 authors = ["marmeladema <xademax@gmail.com>", "Zak Cutner <me@zakcutner.uk>"]
-edition = "2018"
+edition = "2021"
 description = "A fast implementation of single-pattern substring search using SIMD acceleration"
 readme = "README.md"
 repository = "https://github.com/cloudflare/sliceslice-rs"

src/x86.rs

@@ -436,7 +436,7 @@ pub enum DynamicAvx2Searcher<N: Needle> {
 
 macro_rules! array {
     ($c:ident, $S:literal) => [seq!(N in 0..$S {
-            [ #( $c#N, )* ]
+            [ #( $c #N, )* ]
     })];
 }