chore(changelog): add removal of PostgreSQL 12

Author: wolfgangwalther

CHANGELOG.md

@@ -17,6 +17,10 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 - Fix OpenAPI broken docs link by @taimoorzaeem in #4080
 - Fix OpenAPI specification incorrectly exposing GET methods for volatile functions by @joelonsql in #4174
 
+### Changed
+
+- Drop support for PostgreSQL EOL version 12 by @wolfgangwalther in #3865
+
 ## [13.0.4] - 2025-06-17
 
 ### Fixed