Bump asciidoctor from 2.0.20 to 2.0.23

Bumps [asciidoctor](https://github.com/asciidoctor/asciidoctor) from 2.0.20 to 2.0.23.
- [Release notes](https://github.com/asciidoctor/asciidoctor/releases)
- [Changelog](https://github.com/asciidoctor/asciidoctor/blob/main/CHANGELOG.adoc)
- [Commits](asciidoctor/asciidoctor@v2.0.20...v2.0.23)

---
updated-dependencies:
- dependency-name: asciidoctor
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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

Gemfile.lock

@@ -3,7 +3,7 @@ GEM
   specs:
     addressable (2.8.6)
       public_suffix (>= 2.0.2, < 6.0)
-    asciidoctor (2.0.20)
+    asciidoctor (2.0.23)
     asciidoctor-tabs (1.0.0.beta.6)
       asciidoctor (>= 2.0.0, < 3.0.0)
     colorator (1.1.0)