Bump rubocop-rails from 2.20.2 to 2.21.0 in /dependencies (#4640)

Bumps [rubocop-rails](https://github.com/rubocop/rubocop-rails) from 2.20.2 to 2.21.0.
- [Release notes](https://github.com/rubocop/rubocop-rails/releases)
- [Changelog](https://github.com/rubocop/rubocop-rails/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rubocop/rubocop-rails/compare/v2.20.2...v2.21.0)

---
updated-dependencies:
- dependency-name: rubocop-rails
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

dependencies/Gemfile

@@ -8,7 +8,7 @@ gem "rubocop", "~> 1.56.3"
 gem "rubocop-github", "~> 0.20.0"
 gem "rubocop-minitest", "~> 0.31.1"
 gem "rubocop-performance", "~>1.19.0"
-gem "rubocop-rails", "~> 2.20"
+gem "rubocop-rails", "~> 2.21"
 gem "rubocop-rake", "~> 0.6.0"
 gem "rubocop-rspec", "~> 2.24.0"
 gem "standard", "~>1.31"

dependencies/Gemfile.lock

@@ -1,7 +1,7 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    activesupport (7.0.6)
+    activesupport (7.0.8)
       concurrent-ruby (~> 1.0, >= 1.0.2)
       i18n (>= 1.6, < 2)
       minitest (>= 5.1)
@@ -14,7 +14,7 @@ GEM
     json (2.6.3)
     language_server-protocol (3.17.0.3)
     lint_roller (1.1.0)
-    minitest (5.19.0)
+    minitest (5.20.0)
     parallel (1.23.0)
     parser (3.2.2.3)
       ast (~> 2.4.1)
@@ -51,7 +51,7 @@ GEM
     rubocop-performance (1.19.0)
       rubocop (>= 1.7.0, < 2.0)
       rubocop-ast (>= 0.4.0)
-    rubocop-rails (2.20.2)
+    rubocop-rails (2.21.0)
       activesupport (>= 4.2.0)
       rack (>= 1.1)
       rubocop (>= 1.33.0, < 2.0)
@@ -86,7 +86,7 @@ DEPENDENCIES
   rubocop-github (~> 0.20.0)
   rubocop-minitest (~> 0.31.1)
   rubocop-performance (~> 1.19.0)
-  rubocop-rails (~> 2.20)
+  rubocop-rails (~> 2.21)
   rubocop-rake (~> 0.6.0)
   rubocop-rspec (~> 2.24.0)
   standard (~> 1.31)