Update cirrus-actions/rebase action to v1.5

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
cirrus-actions/rebase	action	minor	1.4 -> 1.5

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Release Notes

cirrus-actions/rebase

### [`v1.5`](https://togithub.com/cirrus-actions/rebase/releases/1.5) [Compare Source](https://togithub.com/cirrus-actions/rebase/compare/1.4...1.5) - Allow PR_NUMBER to be set externally ([#​76](https://togithub.com/cirrus-actions/rebase/issues/76)) - Retry if the PR is unrebaseable ([#​75](https://togithub.com/cirrus-actions/rebase/issues/75)) Plus some fixes

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Configuration

📅 Schedule: 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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