tests: Address a Clippy nit.

Author: briansmith

tests/agreement_tests.rs

@@ -38,7 +38,7 @@ fn agreement_traits() {
     test::compile_time_assert_sync::<agreement::EphemeralPrivateKey>();
 
     assert_eq!(
-        format!("{:?}", &private_key),
+        format!("{:?}", private_key),
         "EphemeralPrivateKey { algorithm: Algorithm { curve: P256 } }"
     );
 

tests/hmac_tests.rs

@@ -104,8 +104,8 @@ fn hmac_test_case_inner(
 #[test]
 fn hmac_debug() {
     let key = hmac::Key::new(hmac::HMAC_SHA256, &[0; 32]);
-    assert_eq!("Key { algorithm: SHA256 }", format!("{:?}", &key));
+    assert_eq!("Key { algorithm: SHA256 }", format!("{:?}", key));
 
     let ctx = hmac::Context::with_key(&key);
-    assert_eq!("Context { algorithm: SHA256 }", format!("{:?}", &ctx));
+    assert_eq!("Context { algorithm: SHA256 }", format!("{:?}", ctx));
 }