Prepare release v340 (#2068)

Co-authored-by: heroku-linguist[bot] <136119646+heroku-linguist[bot]@users.noreply.github.com>

Author: heroku-linguist[bot]

CHANGELOG.md

@@ -2,6 +2,9 @@
 
 ## [Unreleased]
 
+
+## [v340] - 2026-04-02
+
 - Updated Pipenv from 2026.0.3 to 2026.5.1. ([#2065](https://github.com/heroku/heroku-buildpack-python/pull/2065))
 - Updated Poetry from 2.3.2 to 2.3.3. ([#2064](https://github.com/heroku/heroku-buildpack-python/pull/2064))
 - Updated uv from 0.10.9 to 0.11.3. ([#2067](https://github.com/heroku/heroku-buildpack-python/pull/2067))
@@ -1505,7 +1508,8 @@ Default Python is now latest 2.7.10. Updated pip and Distribute.
 - Setuptools updated to v16.0
 - pip updated to v7.0.1
 
-[unreleased]: https://github.com/heroku/heroku-buildpack-python/compare/v339...main
+[unreleased]: https://github.com/heroku/heroku-buildpack-python/compare/v340...main
+[v340]: https://github.com/heroku/heroku-buildpack-python/compare/v339...v340
 [v339]: https://github.com/heroku/heroku-buildpack-python/compare/v338...v339
 [v338]: https://github.com/heroku/heroku-buildpack-python/compare/v337...v338
 [v337]: https://github.com/heroku/heroku-buildpack-python/compare/v336...v337