Former where_clauses_object_safety lint is now hard error

Since nightly-2024-06-05.

    warning: unknown lint: `where_clauses_object_safety`
        --> tests/test.rs:1383:8
         |
    1383 | #[deny(where_clauses_object_safety)]
         |        ^^^^^^^^^^^^^^^^^^^^^^^^^^^
         |
         = note: `#[warn(unknown_lints)]` on by default

tests/test.rs

@@ -1380,7 +1380,6 @@ pub mod issue161 {
 }
 
 // https://github.com/dtolnay/async-trait/issues/169
-#[deny(where_clauses_object_safety)]
 pub mod issue169 {
     use async_trait::async_trait;