build(deps): bump dompurify from 2.3.6 to 2.5.6

Bumps [dompurify](https://github.com/cure53/DOMPurify) from 2.3.6 to 2.5.6.
- [Release notes](https://github.com/cure53/DOMPurify/releases)
- [Commits](cure53/DOMPurify@2.3.6...2.5.6)

---
updated-dependencies:
- dependency-name: dompurify
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <support@github.com>