Update CHANGELOG

Author: troyraen

Diff for: CHANGELOG.md

@@ -28,6 +28,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
     - `_str_to_datetime`
 - Add class `alert.MockInput` with support for Cloud Functions
 - Add dependencies `hpgeom` and `google-cloud-functions`.
+- Add `Schema.version_id` (replaces `_header_bytes`) and `Schema._init_from_bytes` to handle
+  cases where `_ConfluentWireAvroSchema` needs to get the schema version from the avro header.
+- Unit tests `test_serialize_without_definition` and `test_unsupported_version_lsst`.
 
 ### Changed
 
@@ -37,10 +40,13 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 - Implement `schema._ConfluentWireAvroSchema.serialize`.
 - Add IDs to `Alert.attributes` the first time it is accessed.
 - Dependencies: Lazy load astropy.
+- Refactor `lsst_schema_helper` to get version from avro header.
+- Update `Alert._prep_for_publish` to call `Schema._init_from_bytes` if needed before serializing.
 
 ### Removed
 
 - Remove `utils.Cast._strip_cutouts_ztf` (moved to `Alert`)
+- Remove `Schema._header_bytes` (replaced by `version_id`).
 
 ## \[v0.3.11\] - 2024-07-22