chore(deps): bump libwebp from 0ab789e to 4c85d86

Bumps [libwebp](https://github.com/webmproject/libwebp) from `0ab789e` to `4c85d86`.
- [Commits](webmproject/libwebp@0ab789e...4c85d86)

---
updated-dependencies:
- dependency-name: libwebp
  dependency-type: direct:production
...

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