Bump rollup from 4.18.1 to 4.19.0 in /apps/webrtc-demo

Bumps [rollup](https://github.com/rollup/rollup) from 4.18.1 to 4.19.0.
- [Release notes](https://github.com/rollup/rollup/releases)
- [Changelog](https://github.com/rollup/rollup/blob/master/CHANGELOG.md)
- [Commits](rollup/rollup@v4.18.1...v4.19.0)

---
updated-dependencies:
- dependency-name: rollup
  dependency-type: indirect
  update-type: version-update:semver-minor
...

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