Ignore needless_pass_by_value Clippy pedantic lint in test suite

    error: this argument is passed by value, but not consumed in the function body
      --> tests/test_macros.rs:65:22
       |
    65 |     fn message(cell: Cell<&str>) -> &str {
       |                      ^^^^^^^^^^ help: consider taking a reference instead: `&Cell<&str>`
       |
       = note: `-D clippy::needless-pass-by-value` implied by `-D clippy::pedantic`
       = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_pass_by_value

Author: dtolnay

tests/test_macros.rs

@@ -1,6 +1,7 @@
 #![allow(
     clippy::eq_op,
     clippy::items_after_statements,
+    clippy::needless_pass_by_value,
     clippy::shadow_unrelated,
     clippy::wildcard_imports
 )]