Bump webrick from 1.8.2 to 1.9.0 (#750)

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

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

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

Gemfile

@@ -8,4 +8,4 @@ gem 'jekyll-last-modified-at'
 gem 'jekyll-paginate-v2'
 gem 'jekyll-redirect-from'
 gem 'jekyll-sitemap'
-gem 'webrick', '~> 1.8'
+gem 'webrick', '~> 1.9'

Gemfile.lock

@@ -78,7 +78,7 @@ GEM
     terminal-table (3.0.2)
       unicode-display_width (>= 1.1.1, < 3)
     unicode-display_width (2.6.0)
-    webrick (1.8.2)
+    webrick (1.9.0)
 
 PLATFORMS
   ruby
@@ -90,7 +90,7 @@ DEPENDENCIES
   jekyll-paginate-v2
   jekyll-redirect-from
   jekyll-sitemap
-  webrick (~> 1.8)
+  webrick (~> 1.9)
 
 BUNDLED WITH
    2.3.22