Update CHANGELOG

Author: troyraen

Diff for: CHANGELOG.md

@@ -18,9 +18,16 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 
 ### Added
 
+- Testing:
+    - Add test data for schema "lsst.v7_4.alert" that is randomly generated.
+    - Add `TestAlertProperties.test_dataframe`. Currently this only tests alerts with schema "lsst.v7_4.alert".
+
 ### Changed
 
 - Add functionality to create DataFrame object when a field's value is `None`
+- Testing:
+    - Move `conftest.SampleAlert` -> `load_data.TestAlert`
+    - Split `TestAlert` -> `TestAlertFrom`, `TestAlertProperties`, and `TestAlertMethods`
 
 ### Removed