resetting CHANGELOG.md for the next release

CHANGELOG.md

@@ -1,16 +1,9 @@
 ## dbt-teradata 1.0.0a
 
 ### Features
-* Addition of new Snapshot features with dbt-teradata v1.9 ([#207](https://github.com/Teradata/dbt-teradata/pull/207)):
-    * Enable setting a datetime value for dbt_valid_to for current records instead of NULL
-    * Enable hard_deletes config to add a metadata column if a record has been deleted
-    * Allow customizing names of metadata fields
-    * Enable unique_key as a list
 
 ### Fixes
-Fixes the exception handling on the valid_history incremental strategy
 
 ### Docs
 
 ### Under the hood
-* Addition of testcases for Snapshot