Bump webrick from 1.8.1 to 1.8.2 in /docs (#226)

Bumps [webrick](https://github.com/ruby/webrick) from 1.8.1 to 1.8.2.
- [Release notes](https://github.com/ruby/webrick/releases)
- [Commits](ruby/webrick@v1.8.1...v1.8.2)

---
updated-dependencies:
- dependency-name: webrick
  dependency-type: direct:production
...

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

Author: dependabot[bot]

docs/Gemfile.lock

@@ -252,7 +252,7 @@ GEM
     unf_ext (0.0.8.2)
     unf_ext (0.0.8.2-x64-mingw32)
     unicode-display_width (1.8.0)
-    webrick (1.8.1)
+    webrick (1.8.2)
 
 PLATFORMS
   ruby