build(deps-dev): bump html-proofer from 3.19.1 to 3.19.2 in /docs

Bumps [html-proofer](https://github.com/gjtorikian/html-proofer) from 3.19.1 to 3.19.2.
- [Release notes](https://github.com/gjtorikian/html-proofer/releases)
- [Commits](https://github.com/gjtorikian/html-proofer/compare/v3.19.1...v3.19.2)

---
updated-dependencies:
- dependency-name: html-proofer
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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

docs/Gemfile.lock

@@ -17,7 +17,7 @@ GEM
     commonmarker (0.17.13)
       ruby-enum (~> 0.5)
     concurrent-ruby (1.1.9)
-    dnsruby (1.61.6)
+    dnsruby (1.61.7)
       simpleidn (~> 0.1)
     em-websocket (0.5.2)
       eventmachine (>= 0.12.9)
@@ -95,7 +95,7 @@ GEM
     html-pipeline (2.14.0)
       activesupport (>= 2)
       nokogiri (>= 1.4)
-    html-proofer (3.19.1)
+    html-proofer (3.19.2)
       addressable (~> 2.3)
       mercenary (~> 0.3)
       nokogumbo (~> 2.0)