Fix Clippy: remove useless (immediately implicitly dereferenced) refs

src/types/audio.rs

@@ -80,7 +80,7 @@ mod tests {
             }),
             file_name: None,
         };
-        let actual = serde_json::from_str::<Audio>(&json).unwrap();
+        let actual = serde_json::from_str::<Audio>(json).unwrap();
         assert_eq!(actual, expected)
     }
 }

src/types/chat_member.rs

@@ -625,7 +625,7 @@ mod tests {
                 can_promote_members: true,
             }),
         };
-        let actual = serde_json::from_str::<ChatMember>(&json).unwrap();
+        let actual = serde_json::from_str::<ChatMember>(json).unwrap();
         assert_eq!(actual, expected)
     }
 }

src/types/user.rs

@@ -66,7 +66,7 @@ mod tests {
             username: Some("Username".to_string()),
             language_code: Some(String::from("ru")),
         };
-        let actual = serde_json::from_str::<User>(&json).unwrap();
+        let actual = serde_json::from_str::<User>(json).unwrap();
         assert_eq!(actual, expected)
     }
 }