Bump rubocop from 0.87.1 to 0.88.0

Bumps [rubocop](https://github.com/rubocop-hq/rubocop) from 0.87.1 to 0.88.0.
- [Release notes](https://github.com/rubocop-hq/rubocop/releases)
- [Changelog](https://github.com/rubocop-hq/rubocop/blob/master/CHANGELOG.md)
- [Commits](rubocop/rubocop@v0.87.1...v0.88.0)

Signed-off-by: dependabot[bot] <support@github.com>

Gemfile.lock

@@ -57,7 +57,7 @@ GEM
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.9.0)
     rspec-support (3.9.3)
-    rubocop (0.87.1)
+    rubocop (0.88.0)
       parallel (~> 1.10)
       parser (>= 2.7.1.1)
       rainbow (>= 2.2.2, < 4.0)