Bump luxon and @11ty/eleventy-plugin-rss

Bumps [luxon](https://github.com/moment/luxon) to 2.5.2 and updates ancestor dependency [@11ty/eleventy-plugin-rss](https://github.com/11ty/eleventy-plugin-rss). These dependencies need to be updated together.


Updates `luxon` from 2.5.0 to 2.5.2
- [Release notes](https://github.com/moment/luxon/releases)
- [Changelog](https://github.com/moment/luxon/blob/master/CHANGELOG.md)
- [Commits](moment/luxon@2.5.0...2.5.2)

Updates `@11ty/eleventy-plugin-rss` from 1.0.7 to 1.2.0
- [Release notes](https://github.com/11ty/eleventy-plugin-rss/releases)
- [Commits](11ty/eleventy-plugin-rss@v1.0.7...v1.2.0)

---
updated-dependencies:
- dependency-name: luxon
  dependency-type: indirect
- dependency-name: "@11ty/eleventy-plugin-rss"
  dependency-type: direct:production
...

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