`Tools/scripts/checkpip.py` is broken

[StanFromIreland]

Bug report

Bug description:

Early last year, ensurepip._PROJECTS was removed in 9639043 breaking the script.

I do not know if it is worth fixing the script, or if it should just be removed since no one has noticed indicating that it is not used.

cc @ncoghlan

CPython versions tested on:

CPython main branch

Operating systems tested on:

No response

Linked PRs

• gh-139198: Remove Tools/scripts/checkpip.py script #139199

[ncoghlan]

It can just go - pip has its own freshness check, so this was only useful when there were multiple bundled wheels to check.

[AA-Turner]

It might be a useful thing to add to our release checklist (perhaps to PEP 101)? cc @hugovk as RM.

I believe updating ensurepip is part of the release process from the pip maintainers' perspective, but if we're removing this script it could be useful to double check that the latest version is bundled on our side.

A