Bump webrick from 1.7.0 to 1.8.1

Bumps [webrick](https://github.com/ruby/webrick) from 1.7.0 to 1.8.1.
- [Release notes](https://github.com/ruby/webrick/releases)
- [Commits](ruby/webrick@v1.7.0...v1.8.1)

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

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

Author: dependabot[bot]

Gemfile

@@ -13,4 +13,4 @@ gem 'kramdown-parser-gfm'
 # and do:
 # bundle exec jekyll liveserve --incremental
 
-gem "webrick", "~> 1.7"
+gem "webrick", "~> 1.8"

Gemfile.lock

@@ -79,7 +79,7 @@ GEM
     typhoeus (1.4.0)
       ethon (>= 0.9.0)
     unicode-display_width (1.8.0)
-    webrick (1.7.0)
+    webrick (1.8.1)
     yell (2.2.2)
 
 PLATFORMS
@@ -91,7 +91,7 @@ DEPENDENCIES
   html-proofer
   jekyll-redirect-from
   kramdown-parser-gfm
-  webrick (~> 1.7)
+  webrick (~> 1.8)
 
 BUNDLED WITH
    2.3.10