Merge #827

827: Remove unused macro rules r=taiki-e a=alygin

The [new `unused_macro_rules` lint](rust-lang/rust#73576) that recently landed in nightly [breaks](https://github.com/crossbeam-rs/crossbeam/actions/runs/2316949414) CI builds.

This fix removes unused macro arms in tests.

Co-authored-by: Andrew Lygin <alygin@gmail.com>

crossbeam-channel/tests/golang.rs

@@ -238,14 +238,6 @@ macro_rules! defer {
 }
 
 macro_rules! go {
-    (@parse ref $v:ident, $($tail:tt)*) => {{
-        let ref $v = $v;
-        go!(@parse $($tail)*)
-    }};
-    (@parse move $v:ident, $($tail:tt)*) => {{
-        let $v = $v;
-        go!(@parse $($tail)*)
-    }};
     (@parse $v:ident, $($tail:tt)*) => {{
         let $v = $v.clone();
         go!(@parse $($tail)*)