Bump http-cache-semantics from 4.1.0 to 4.1.1 in /demo

Bumps [http-cache-semantics](https://github.com/kornelski/http-cache-semantics) from 4.1.0 to 4.1.1.
- [Release notes](https://github.com/kornelski/http-cache-semantics/releases)
- [Commits](kornelski/http-cache-semantics@v4.1.0...v4.1.1)

---
updated-dependencies:
- dependency-name: http-cache-semantics
  dependency-type: indirect
...

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Author: dependabot[bot]