Ignore unused_parens warning in test

    warning: unnecessary parentheses around type
       --> tests/test.rs:904:20
        |
    904 |     impl Trait for (dyn Fn(u8) + Send + Sync) {
        |                    ^                        ^
        |
        = note: `#[warn(unused_parens)]` on by default
    help: remove these parentheses
        |
    904 -     impl Trait for (dyn Fn(u8) + Send + Sync) {
    904 +     impl Trait for dyn Fn(u8) + Send + Sync {
        |

Author: dtolnay

tests/test.rs

@@ -881,7 +881,7 @@ pub mod issue87 {
 
 // https://github.com/dtolnay/async-trait/issues/89
 pub mod issue89 {
-    #![allow(bare_trait_objects)]
+    #![allow(bare_trait_objects, unused_parens)]
 
     use async_trait::async_trait;