Bump json from 2.7.6 to 2.8.1

Bumps [json](https://github.com/ruby/json) from 2.7.6 to 2.8.1.
- [Release notes](https://github.com/ruby/json/releases)
- [Changelog](https://github.com/ruby/json/blob/master/CHANGES.md)
- [Commits](ruby/json@v2.7.6...v2.8.1)

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

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

Gemfile

@@ -9,4 +9,4 @@ gem "webrick", "~> 1.9"
 
 gem "pathutil", "~> 0.16.2"
 
-gem "json", "~> 2.7"
+gem "json", "~> 2.8"

Gemfile.lock

@@ -65,7 +65,7 @@ GEM
       sass-embedded (~> 1.54)
     jekyll-watch (2.2.1)
       listen (~> 3.0)
-    json (2.7.6)
+    json (2.8.1)
     kramdown (2.4.0)
       rexml
     kramdown-parser-gfm (1.1.0)
@@ -142,7 +142,7 @@ PLATFORMS
 DEPENDENCIES
   jekyll (>= 3.6.3)
   jekyll-feed
-  json (~> 2.7)
+  json (~> 2.8)
   neat (>= 1.0.0)
   pathutil (~> 0.16.2)
   webrick (~> 1.9)