Prepare release v277 (#1750)

* Prepare release v277

* Update changelog

---------

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

Author: heroku-linguist[bot]

CHANGELOG.md

@@ -2,11 +2,15 @@
 
 ## [Unreleased]
 
+
+## [v277] - 2025-02-17
+
 - Improved the warning message shown when the requested Python version is not the latest patch version. ([#1749](https://github.com/heroku/heroku-buildpack-python/pull/1749))
 - Improved the error message shown when the requested Python patch version isn't available. ([#1749](https://github.com/heroku/heroku-buildpack-python/pull/1749))
 - Improved the error message shown if there was a networking or server related error downloading Python. ([#1749](https://github.com/heroku/heroku-buildpack-python/pull/1749))
 - Adjusted the curl options used when downloading Python to set a maximum download time of 120s to prevent hanging builds in the case of network issues. ([#1749](https://github.com/heroku/heroku-buildpack-python/pull/1749))
 - Refactored the Python download step to avoid an unnecessary version check `HEAD` request to S3 prior to downloading Python or reusing a cached install. ([#1749](https://github.com/heroku/heroku-buildpack-python/pull/1749))
+- Updated the `runtime.txt` deprecation warning to include a link to the deprecation changelog post. ([#1747](https://github.com/heroku/heroku-buildpack-python/pull/1747))
 - Improved buildpack metrics for Python version selection. ([#1749](https://github.com/heroku/heroku-buildpack-python/pull/1749))
 - Improved buildpack metrics for builds that fail. ([#1746](https://github.com/heroku/heroku-buildpack-python/pull/1746) and [#1749](https://github.com/heroku/heroku-buildpack-python/pull/1749))
 
@@ -1164,7 +1168,8 @@ 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/v276...main
+[unreleased]: https://github.com/heroku/heroku-buildpack-python/compare/v277...main
+[v277]: https://github.com/heroku/heroku-buildpack-python/compare/v276...v277
 [v276]: https://github.com/heroku/heroku-buildpack-python/compare/v275...v276
 [v275]: https://github.com/heroku/heroku-buildpack-python/compare/v274...v275
 [v274]: https://github.com/heroku/heroku-buildpack-python/compare/v273...v274