Bump rubocop from 0.53.0 to 0.54.0

Bumps [rubocop](https://github.com/bbatsov/rubocop) from 0.53.0 to 0.54.0.
- [Release notes](https://github.com/bbatsov/rubocop/releases)
- [Changelog](https://github.com/bbatsov/rubocop/blob/master/CHANGELOG.md)
- [Commits](rubocop/rubocop@v0.53.0...v0.54.0)

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

Gemfile.lock

@@ -86,7 +86,7 @@ GEM
     octokit (4.7.0)
       sawyer (~> 0.8.0, >= 0.5.3)
     parallel (1.12.1)
-    parser (2.5.0.2)
+    parser (2.5.0.4)
       ast (~> 2.4.0)
     pathutil (0.16.1)
       forwardable-extended (~> 2.6)
@@ -112,7 +112,7 @@ GEM
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.7.0)
     rspec-support (3.7.0)
-    rubocop (0.53.0)
+    rubocop (0.54.0)
       parallel (~> 1.10)
       parser (>= 2.5)
       powerpack (~> 0.1)