Bump lit-html from 1.4.1 to 2.2.7 in /assets

Bumps [lit-html](https://github.com/lit/lit/tree/HEAD/packages/lit-html) from 1.4.1 to 2.2.7.
- [Release notes](https://github.com/lit/lit/releases)
- [Changelog](https://github.com/lit/lit/blob/main/packages/lit-html/CHANGELOG.md)
- [Commits](https://github.com/lit/lit/commits/lit-html@2.2.7/packages/lit-html)

---
updated-dependencies:
- dependency-name: lit-html
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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