Bump @feelpp/asciidoctor-extensions from 1.0.0-rc.5 to 1.0.0-rc.8

Bumps [@feelpp/asciidoctor-extensions](https://github.com/feelpp/feelpp-asciidoctor-extensions) from 1.0.0-rc.5 to 1.0.0-rc.8.
- [Release notes](https://github.com/feelpp/feelpp-asciidoctor-extensions/releases)
- [Commits](feelpp/feelpp-asciidoctor-extensions@v1.0.0-rc.5...v1.0.0-rc.8)

---
updated-dependencies:
- dependency-name: "@feelpp/asciidoctor-extensions"
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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