Update release version (#2327)

Author: sfc-gh-mmishchenko

DESCRIPTION.md

@@ -7,7 +7,7 @@ https://docs.snowflake.com/
 Source code is also available at: https://github.com/snowflakedb/snowflake-connector-python
 
 # Release Notes
-- v3.16(TBD)
+- v3.15.1(May 20, 2025)
   - Added basic arrow support for Interval types.
   - Fix `write_pandas` special characters usage in the location name.
   - Fix usage of `use_virtual_url` when building the location for gcs storage client.