Update rubocop-performance requirement from ~> 1.19.1 to ~> 1.20.1

Updates the requirements on [rubocop-performance](https://github.com/rubocop/rubocop-performance) to permit the latest version.
- [Release notes](https://github.com/rubocop/rubocop-performance/releases)
- [Changelog](https://github.com/rubocop/rubocop-performance/blob/master/CHANGELOG.md)
- [Commits](rubocop/rubocop-performance@v1.19.1...v1.20.1)

---
updated-dependencies:
- dependency-name: rubocop-performance
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <support@github.com>

cloudflare-rails.gemspec

@@ -26,7 +26,7 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency 'rspec_junit_formatter', '~> 0.6.0'
   spec.add_development_dependency 'rspec-rails', '~> 6.1.0'
   spec.add_development_dependency 'rubocop', '~> 1.59.0'
-  spec.add_development_dependency 'rubocop-performance', '~> 1.19.1'
+  spec.add_development_dependency 'rubocop-performance', '~> 1.20.1'
   spec.add_development_dependency 'rubocop-rails', '~> 2.22.2'
   spec.add_development_dependency 'rubocop-rspec', '~> 2.25.0'
   spec.add_development_dependency 'webmock', '~> 3.19.1'