Update dependency rackup to v2.2.1

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
rackup	'2.2.0' -> '2.2.1'

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Release Notes

rack/rackup (rackup)

### [`v2.2.1`](https://redirect.github.com/rack/rackup/compare/v2.2.0...v2.2.1) [Compare Source](https://redirect.github.com/rack/rackup/compare/v2.2.0...v2.2.1)

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Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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• [ ] If you want to rebase/retry this PR, check this box

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[yegor256]

@rultor please, try to merge, since 4 checks have passed

[rultor]

@rultor please, try to merge, since 4 checks have passed

@yegor256 OK, I'll try to merge now. You can check the progress of the merge here.

[rultor]

@rultor please, try to merge, since 4 checks have passed

@yegor256 Done! FYI, the full log is here (took me 10min).