Prepare release v0.7.3 (#139)

## heroku/python

### Changed

- Updated wheel from 0.41.2 to 0.41.3. ([#137](#137))

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

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.7.3] - 2023-11-06
+
 ### Changed
 
 - Updated wheel from 0.41.2 to 0.41.3. ([#137](https://github.com/heroku/buildpacks-python/pull/137))
@@ -84,7 +86,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Initial implementation. ([#3](https://github.com/heroku/buildpacks-python/pull/3))
 
-[unreleased]: https://github.com/heroku/buildpacks-python/compare/v0.7.2...HEAD
+[unreleased]: https://github.com/heroku/buildpacks-python/compare/v0.7.3...HEAD
+[0.7.3]: https://github.com/heroku/buildpacks-python/compare/v0.7.2...v0.7.3
 [0.7.2]: https://github.com/heroku/buildpacks-python/compare/v0.7.1...v0.7.2
 [0.7.1]: https://github.com/heroku/buildpacks-python/compare/v0.7.0...v0.7.1
 [0.7.0]: https://github.com/heroku/buildpacks-python/compare/v0.6.0...v0.7.0

buildpack.toml

@@ -2,7 +2,7 @@ api = "0.9"
 
 [buildpack]
 id = "heroku/python"
-version = "0.7.2"
+version = "0.7.3"
 name = "Heroku Python"
 homepage = "https://github.com/heroku/buildpacks-python"
 description = "Heroku's buildpack for Python applications."