Update rubocop requirement from = 1.56.3 to = 1.56.4

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@v1.56.3...v1.56.4)

---
updated-dependencies:
- dependency-name: rubocop
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

Gemfile.lock

@@ -68,7 +68,7 @@ GEM
     rake (13.0.6)
     regexp_parser (2.8.1)
     rexml (3.2.6)
-    rubocop (1.56.3)
+    rubocop (1.56.4)
       base64 (~> 0.1.1)
       json (~> 2.3)
       language_server-protocol (>= 3.17.0)
@@ -98,7 +98,7 @@ GEM
     smart_properties (1.17.0)
     tzinfo (2.0.6)
       concurrent-ruby (~> 1.0)
-    unicode-display_width (2.4.2)
+    unicode-display_width (2.5.0)
 
 PLATFORMS
   ruby
@@ -109,7 +109,7 @@ DEPENDENCIES
   minitest (~> 5.20.0)
   mocha (~> 2.1.0)
   rake (~> 13.0.6)
-  rubocop (= 1.56.3)
+  rubocop (= 1.56.4)
   rubocop-github (~> 0.20.0)
 
 BUNDLED WITH

erblint-github.gemspec

@@ -21,7 +21,7 @@ Gem::Specification.new do |s|
   s.add_development_dependency "mocha", "~> 2.1.0"
   s.add_development_dependency "rake", "~> 13.0.6"
 
-  s.add_development_dependency "rubocop", "= 1.56.3"
+  s.add_development_dependency "rubocop", "= 1.56.4"
   s.add_development_dependency "rubocop-github", "~> 0.20.0"
   s.metadata["rubygems_mfa_required"] = "true"