automatically generate PRs to upgrade PyPy and CPython in our release process

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We have recently ( #12083 ) updated to pinning PyPy version, and we should keep it that way so that buggy pypy upgrades do not disrupt unrelated changes getting landed, but we should have automatic PRs for new versions of PyPy.

I don't think dependabot can generate these and I haven't found anything automatic yet, but a daily cron job to check if the version has changed on the website and try editing the yaml and opening a PR should do the trick.

[adiroiban]

I don't think pypy breakage is that often.
And if it happens, we can fix it by temporary pinning the previous PyPy version.
The devs from PyPy were quite responsive.

For me, the macos flaky tests are a much bigger issue than PyPy.

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For me, the macos flaky tests are a much bigger issue than PyPy.

This is not an issue of prioritization, but, I've been banging on the CFReactor tests to try to understand what's going on there too.

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I don't think pypy breakage is that often.
And if it happens, we can fix it by temporary pinning the previous PyPy version.

I don't want new contributors to get test failures that are not related to their change. Everything should be pinned, as a matter of course. PyPy is among the least likely to cause issues, but luckily, it's already pinned so nothing needs to be done there :).

We need a similar pinning & cron job for CPython upgrades as well, so PyPy isn't special here, the example is just recent and so this issue tracks a follow-up.