Bump sharp and @11ty/eleventy-img (#538)

Bumps [sharp](https://github.com/lovell/sharp) to 0.32.6 and updates ancestor dependency [@11ty/eleventy-img](https://github.com/11ty/eleventy-img). These dependencies need to be updated together.


Updates `sharp` from 0.31.3 to 0.32.6
- [Release notes](https://github.com/lovell/sharp/releases)
- [Changelog](https://github.com/lovell/sharp/blob/main/docs/changelog.md)
- [Commits](lovell/sharp@v0.31.3...v0.32.6)

Updates `@11ty/eleventy-img` from 3.0.0 to 3.1.8
- [Release notes](https://github.com/11ty/eleventy-img/releases)
- [Commits](11ty/eleventy-img@v3.0.0...v3.1.8)

---
updated-dependencies:
- dependency-name: sharp
  dependency-type: indirect
- dependency-name: "@11ty/eleventy-img"
  dependency-type: direct:development
...

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