Prepare release v257

[heroku-linguist]

Commits since the last release:

• Fix duplicate word in binary build script error messages (Fix duplicate word in binary build script error messages #1635)
• Improve make run (Improve make run #1636)
• Misc integration test improvements (Misc integration test improvements #1634)
• Add more files to the buildpack publishing file exclusion list (Add more files to the buildpack publishing file exclusion list #1637)
• Format shell scripts using shfmt (Format shell scripts using shfmt #1638)
• Switch to a new output helper for error messages (Switch to a new output helper for error messages #1639)
• Refactor package manager handling (Refactor package manager handling #1640)

For the full diff, see the compare view:
v256...main

[edmorley]

$ make publish
Deploy as version: v257 [y/n]? y

Tagging commit 54940fd175434907abb7cf35fa9d5f6eca061852 with v257... 
Total 0 (delta 0), reused 0 (delta 0), pack-reused 0 (from 0)
To https://github.com/heroku/heroku-buildpack-python
 * [new tag]         v257 -> v257

Publishing to the buildpack registry...
Two-factor code: ********************************************
Publishing buildpack heroku/python... done
Publishing buildpack was successful

 Version Released At              Status    
 ─────── ──────────────────────── ───────── 
 257     2024-09-24T17:53:06.818Z published