chore(deps-dev): update rubocop requirement from = 1.63.5 to = 1.64.0 (#559)

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@v1.63.5...v1.64.0)

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

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

Author: dependabot[bot]

appium_lib_core.gemspec

@@ -29,7 +29,7 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency 'minitest-reporters', '~> 1.1'
   spec.add_development_dependency 'parallel_tests'
   spec.add_development_dependency 'rake', '~> 13.0'
-  spec.add_development_dependency 'rubocop', '1.63.5'
+  spec.add_development_dependency 'rubocop', '1.64.0'
   spec.add_development_dependency 'simplecov'
   spec.add_development_dependency 'webmock', '~> 3.23.0'
   spec.add_development_dependency 'yard', '~> 0.9.11'