Update jekyll requirement from ~> 4.2.0 to ~> 4.3.3

Updates the requirements on [jekyll](https://github.com/jekyll/jekyll) to permit the latest version.
- [Release notes](https://github.com/jekyll/jekyll/releases)
- [Changelog](https://github.com/jekyll/jekyll/blob/master/History.markdown)
- [Commits](jekyll/jekyll@v4.2.0...v4.3.3)

---
updated-dependencies:
- dependency-name: jekyll
  dependency-type: direct:production
...

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

Gemfile

@@ -1,5 +1,5 @@
 source "https://rubygems.org"
-gem "jekyll", "~> 4.2.0"
+gem "jekyll", "~> 4.3.3"
 
 group :jekyll_plugins do
   gem "jekyll-scholar"