Bump webrick from 1.7.0 to 1.8.2 in /docs (#431)

Bumps [webrick](https://github.com/ruby/webrick) from 1.7.0 to 1.8.2.
- [Release notes](https://github.com/ruby/webrick/releases)
- [Commits](ruby/webrick@v1.7.0...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>

docs/Gemfile

@@ -33,4 +33,4 @@ gem "wdm", "~> 0.1.1", :platforms => [:mingw, :x64_mingw, :mswin]
 # do not have a Java counterpart.
 gem "http_parser.rb", "~> 0.6.0", :platforms => [:jruby]
 
-gem "webrick", "~> 1.7"
+gem "webrick", "~> 1.8"

docs/Gemfile.lock

@@ -261,7 +261,7 @@ GEM
     unf_ext (0.0.9.1-x64-mingw-ucrt)
     unicode-display_width (1.8.0)
     wdm (0.1.1)
-    webrick (1.7.0)
+    webrick (1.8.2)
 
 PLATFORMS
   x64-mingw-ucrt
@@ -275,7 +275,7 @@ DEPENDENCIES
   tzinfo (>= 1, < 3)
   tzinfo-data
   wdm (~> 0.1.1)
-  webrick (~> 1.7)
+  webrick (~> 1.8)
 
 BUNDLED WITH
    2.3.26