Update rubocop requirement from = 1.63.5 to = 1.64.0 (#34)

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
  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>

Gemfile.lock

@@ -46,7 +46,7 @@ GEM
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.13.0)
     rspec-support (3.13.1)
-    rubocop (1.63.5)
+    rubocop (1.64.0)
       json (~> 2.3)
       language_server-protocol (>= 3.17.0)
       parallel (~> 1.10)
@@ -72,7 +72,7 @@ DEPENDENCIES
   meowcop (= 3.2.0)
   rake (= 13.2.1)
   rspec (= 3.13.0)
-  rubocop (= 1.63.5)
+  rubocop (= 1.64.0)
 
 BUNDLED WITH
    2.4.21

incr.gemspec

@@ -26,6 +26,6 @@ Gem::Specification.new do |spec|
 
   spec.add_development_dependency('rake', '13.2.1')
   spec.add_development_dependency('rspec', '3.13.0')
-  spec.add_development_dependency('rubocop', '1.63.5')
+  spec.add_development_dependency('rubocop', '1.64.0')
   spec.add_development_dependency('meowcop', '3.2.0')
 end