Bump dns-packet from 1.3.1 to 1.3.4 in /demo (#26)

Bumps [dns-packet](https://github.com/mafintosh/dns-packet) from 1.3.1 to 1.3.4.
- [Release notes](https://github.com/mafintosh/dns-packet/releases)
- [Changelog](https://github.com/mafintosh/dns-packet/blob/master/CHANGELOG.md)
- [Commits](mafintosh/dns-packet@v1.3.1...v1.3.4)

Signed-off-by: dependabot[bot] <[email protected]>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>