Update rubocop requirement from ~> 1.62.1 to ~> 1.63.4 (#237)

Updates the requirements on [rubocop](https://github.com/rubocop/rubocop) to permit the latest version.
- [Release notes](https://github.com/rubocop/rubocop/releases)
- [Changelog](https://github.com/rubocop/rubocop/blob/master/CHANGELOG.md)
- [Commits](rubocop/rubocop@v1.62.1...v1.63.4)

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

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

Gemfile

@@ -13,7 +13,7 @@ end
 
 group :development do
   gem 'yard', '~> 0.9.36', require: false
-  gem 'rubocop', '~> 1.62.1', require: false
+  gem 'rubocop', '~> 1.63.4', require: false
 end
 
 group :test do