Bump css-vars-ponyfill from 2.4.5 to 2.4.6

Bumps [css-vars-ponyfill](https://github.com/jhildenbiddle/css-vars-ponyfill) from 2.4.5 to 2.4.6.
- [Release notes](https://github.com/jhildenbiddle/css-vars-ponyfill/releases)
- [Changelog](https://github.com/jhildenbiddle/css-vars-ponyfill/blob/master/CHANGELOG.md)
- [Commits](jhildenbiddle/css-vars-ponyfill@v2.4.5...v2.4.6)

---
updated-dependencies:
- dependency-name: css-vars-ponyfill
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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