Bump cirrus-actions/rebase from 1.7 to 1.8

Bumps [cirrus-actions/rebase](https://github.com/cirrus-actions/rebase) from 1.7 to 1.8.
- [Release notes](https://github.com/cirrus-actions/rebase/releases)
- [Commits](https://github.com/cirrus-actions/rebase/compare/6e572f08c244e2f04f9beb85a943eb618218714d...b87d48154a87a85666003575337e27b8cd65f691

)

---
updated-dependencies:
- dependency-name: cirrus-actions/rebase
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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