Bumps [actions/checkout](https://github.com/actions/checkout) from 5 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](https://github.com/actions/checkout/compare/v5...v6)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

There are no source code files in this repository, so a separate clang
build is unnecessary.

Replace Travis CI configuration with GitHub Actions workflows.
Add CI build workflow for Debian, Fedora, Ubuntu, and Archlinux.
Add release workflow for automated GitHub releases on tags.
Add dependabot configuration for GHA pin updates.
Remove obsolete .travis.yml.