Bump webrick in /public in the dependencies group across 1 directory

Bumps the dependencies group with 1 update in the /public directory: [webrick](https://github.com/ruby/webrick).


Updates `webrick` from 1.8.2 to 1.9.1
- [Release notes](https://github.com/ruby/webrick/releases)
- [Commits](ruby/webrick@v1.8.2...v1.9.1)

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

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

Author: dependabot[bot]

public/Gemfile

@@ -14,5 +14,5 @@ end
 gem "wdm", "~> 0.1.1", :platforms => [:mingw, :x64_mingw, :mswin]
 
 # Fix jekyll serve for ruby 3.0.0
-gem "webrick", "~> 1.8"
+gem "webrick", "~> 1.9"