build(deps): bump pycairo from 1.20.1 to 1.21.0 (#534)

Bumps [pycairo](https://github.com/pygobject/pycairo) from 1.20.1 to 1.21.0.
- [Release notes](https://github.com/pygobject/pycairo/releases)
- [Changelog](https://github.com/pygobject/pycairo/blob/master/NEWS)
- [Commits](https://github.com/pygobject/pycairo/compare/v1.20.1...v1.21.0)

---
updated-dependencies:
- dependency-name: pycairo
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

scripts/KlipperScreen-requirements.txt

@@ -4,5 +4,5 @@ matplotlib==3.5.0
 netifaces==0.11.0
 requests==2.27.1
 websocket-client==1.3.1
-pycairo==1.20.1
+pycairo==1.21.0
 PyGObject==3.42.0