style: Silence dead_code warning for PartialRead struct

The PartialRead struct in reader_test.rs intentionally leaves some fields unread to test serde::de::IgnoredAny. This commit adds #[allow(dead_code)] to the struct to silence the associated compiler warning, indicating that the unused fields are intentional for testing purposes.

Author: oschwald

src/reader_test.rs

@@ -1212,6 +1212,7 @@ fn test_ignored_any() {
     let _ = env_logger::try_init();
 
     // Struct that only reads some fields, ignoring others via IgnoredAny
+    #[allow(dead_code)]
     #[derive(Deserialize, Debug)]
     struct PartialRead {
         utf8_string: String,