Bump rubocop-govuk from 4.1.0 to 4.2.0

Bumps [rubocop-govuk](https://github.com/alphagov/rubocop-govuk) from 4.1.0 to 4.2.0.
- [Release notes](https://github.com/alphagov/rubocop-govuk/releases)
- [Changelog](https://github.com/alphagov/rubocop-govuk/blob/main/CHANGELOG.md)
- [Commits](alphagov/rubocop-govuk@v4.1.0...v4.2.0)

---
updated-dependencies:
- dependency-name: rubocop-govuk
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

Gemfile.lock

@@ -294,32 +294,31 @@ GEM
     rexml (3.2.5)
     robotex (1.0.0)
     rouge (3.26.1)
-    rubocop (1.21.0)
+    rubocop (1.23.0)
       parallel (~> 1.10)
       parser (>= 3.0.0.0)
       rainbow (>= 2.2.2, < 4.0)
       regexp_parser (>= 1.8, < 3.0)
       rexml
-      rubocop-ast (>= 1.9.1, < 2.0)
+      rubocop-ast (>= 1.12.0, < 2.0)
       ruby-progressbar (~> 1.7)
       unicode-display_width (>= 1.4.0, < 3.0)
-    rubocop-ast (1.11.0)
+    rubocop-ast (1.13.0)
       parser (>= 3.0.1.1)
-    rubocop-govuk (4.1.0)
-      rubocop (= 1.21.0)
-      rubocop-ast (= 1.11.0)
-      rubocop-rails (= 2.12.2)
+    rubocop-govuk (4.2.0)
+      rubocop (= 1.23.0)
+      rubocop-ast (= 1.13.0)
+      rubocop-rails (= 2.12.4)
       rubocop-rake (= 0.6.0)
-      rubocop-rspec (= 2.4.0)
-    rubocop-rails (2.12.2)
+      rubocop-rspec (= 2.6.0)
+    rubocop-rails (2.12.4)
       activesupport (>= 4.2.0)
       rack (>= 1.1)
       rubocop (>= 1.7.0, < 2.0)
     rubocop-rake (0.6.0)
       rubocop (~> 1.0)
-    rubocop-rspec (2.4.0)
-      rubocop (~> 1.0)
-      rubocop-ast (>= 1.1.0)
+    rubocop-rspec (2.6.0)
+      rubocop (~> 1.19)
     ruby-progressbar (1.11.0)
     ruby2_keywords (0.0.5)
     rubyzip (2.3.0)