Bump sharp from 0.35.3 to 0.35.4 in /docs

Bumps [sharp](https://github.com/lovell/sharp) from 0.35.3 to 0.35.4.
- [Release notes](https://github.com/lovell/sharp/releases)
- [Commits](lovell/sharp@v0.35.3...v0.35.4)

---
updated-dependencies:
- dependency-name: sharp
  dependency-version: 0.35.4
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Author: dependabot[bot]