Bump rails-html-sanitizer from 1.4.2 to 1.4.3 (#1781)

Bumps [rails-html-sanitizer](https://github.com/rails/rails-html-sanitizer) from 1.4.2 to 1.4.3.
- [Release notes](https://github.com/rails/rails-html-sanitizer/releases)
- [Changelog](https://github.com/rails/rails-html-sanitizer/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rails/rails-html-sanitizer/compare/v1.4.2...v1.4.3)

---
updated-dependencies:
- dependency-name: rails-html-sanitizer
  dependency-type: indirect
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Gemfile.lock

@@ -221,7 +221,7 @@ GEM
     rails-dom-testing (2.0.3)
       activesupport (>= 4.2.0)
       nokogiri (>= 1.6)
-    rails-html-sanitizer (1.4.2)
+    rails-html-sanitizer (1.4.3)
       loofah (~> 2.3)
     rails-perftest (0.0.7)
     railties (5.2.8)