Ignore extra_unused_type_parameters clippy lint in test

    error: type parameter goes unused in function definition
     --> tests/macros.rs:3:16
      |
    3 | fn assert_clone<T: Clone>() {}
      |                ^^^^^^^^^^
      |
      = help: consider removing the parameter
      = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#extra_unused_type_parameters
      = note: `-D clippy::extra-unused-type-parameters` implied by `-D clippy::all`

tests/macros.rs

@@ -1,3 +1,5 @@
+#![allow(clippy::extra_unused_type_parameters)]
+
 use dyn_clone::{clone_trait_object, DynClone};
 
 fn assert_clone<T: Clone>() {}