build(deps-dev): update html-proofer requirement from ~> 3.19.4 to ~>…

… 4.4.3

Updates the requirements on [html-proofer](https://github.com/gjtorikian/html-proofer) to permit the latest version.
- [Release notes](https://github.com/gjtorikian/html-proofer/releases)
- [Changelog](https://github.com/gjtorikian/html-proofer/blob/main/CHANGELOG.md)
- [Commits](gjtorikian/html-proofer@v3.19.4...v4.4.3)

---
updated-dependencies:
- dependency-name: html-proofer
  dependency-type: direct:development
...

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

Gemfile

@@ -3,6 +3,6 @@ source "https://rubygems.org"
 gem "github-pages", group: :jekyll_plugins
 
 group :test do
-  gem "html-proofer", "~> 3.19.4"
+  gem "html-proofer", "~> 4.4.3"
   gem "rake"
 end