Bump rubocop from 1.55.1 to 1.56.0

Bumps [rubocop](https://github.com/rubocop/rubocop) from 1.55.1 to 1.56.0.
- [Release notes](https://github.com/rubocop/rubocop/releases)
- [Changelog](https://github.com/rubocop/rubocop/blob/master/CHANGELOG.md)
- [Commits](rubocop/rubocop@v1.55.1...v1.56.0)

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

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

Author: dependabot[bot]

Diff for: Gemfile.lock

@@ -8,6 +8,7 @@ GEM
   remote: https://rubygems.org/
   specs:
     ast (2.4.2)
+    base64 (0.1.1)
     docile (1.4.0)
     json (2.6.3)
     language_server-protocol (3.17.0.3)
@@ -22,7 +23,8 @@ GEM
     rake (13.0.6)
     regexp_parser (2.8.1)
     rexml (3.2.6)
-    rubocop (1.55.1)
+    rubocop (1.56.0)
+      base64 (~> 0.1.1)
       json (~> 2.3)
       language_server-protocol (>= 3.17.0)
       parallel (~> 1.10)