Bump webrick from 1.8.2 to 1.9.0 in /docs in the all-gems group across 1 directory (#5308)

Bump webrick in /docs in the all-gems group across 1 directory

Bumps the all-gems group with 1 update in the /docs directory: [webrick](https://github.com/ruby/webrick).


Updates `webrick` from 1.8.2 to 1.9.0
- [Release notes](https://github.com/ruby/webrick/releases)
- [Commits](https://github.com/ruby/webrick/compare/v1.8.2...v1.9.0)

---
updated-dependencies:
- dependency-name: webrick
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: all-gems
...

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

docs/Gemfile.lock

@@ -266,7 +266,7 @@ GEM
       concurrent-ruby (~> 1.0)
     unicode-display_width (1.8.0)
     uri (0.13.1)
-    webrick (1.8.2)
+    webrick (1.9.0)
 
 PLATFORMS
   x86_64-linux