build(deps): bump .git_submodules/sweet-theme

Bumps [.git_submodules/sweet-theme](https://github.com/EliverLara/Sweet) from `d04cbc2` to `dffa6c6`.
- [Release notes](https://github.com/EliverLara/Sweet/releases)
- [Commits](EliverLara/Sweet@d04cbc2...dffa6c6)

---
updated-dependencies:
- dependency-name: ".git_submodules/sweet-theme"
  dependency-type: direct:production
...

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