Bump govuk-lint from 4.2.0 to 4.3.0

Bumps [govuk-lint](https://github.com/alphagov/govuk-lint) from 4.2.0 to 4.3.0.
- [Release notes](https://github.com/alphagov/govuk-lint/releases)
- [Changelog](https://github.com/alphagov/govuk-lint/blob/master/CHANGELOG.md)
- [Commits](alphagov/govuk-lint@v4.2.0...v4.3.0)

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

Author: dependabot-preview[bot]

Gemfile.lock

@@ -100,7 +100,7 @@ GEM
       rest-client (~> 2.0)
     globalid (0.4.2)
       activesupport (>= 4.2.0)
-    govuk-lint (4.2.0)
+    govuk-lint (4.3.0)
       rubocop (~> 0.76)
       rubocop-rails (~> 2)
       rubocop-rspec (~> 1.28)