Bump rubocop from 1.12.1 to 1.13.0 (#125)

Bumps [rubocop](https://github.com/rubocop/rubocop) from 1.12.1 to 1.13.0.
- [Release notes](https://github.com/rubocop/rubocop/releases)
- [Changelog](https://github.com/rubocop/rubocop/blob/master/CHANGELOG.md)
- [Commits](rubocop/rubocop@v1.12.1...v1.13.0)

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

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Gemfile.lock

@@ -96,7 +96,7 @@ GEM
       multi_xml (~> 0.5)
       rack (>= 1.2, < 3)
     parallel (1.20.1)
-    parser (3.0.0.0)
+    parser (3.0.1.0)
       ast (~> 2.4.1)
     pg (1.2.3)
     pry (0.14.1)
@@ -123,7 +123,7 @@ GEM
     rchardet (1.8.0)
     rdoc (6.2.1)
     regexp_parser (2.1.1)
-    rexml (3.2.4)
+    rexml (3.2.5)
     rspec (3.10.0)
       rspec-core (~> 3.10.0)
       rspec-expectations (~> 3.10.0)
@@ -137,7 +137,7 @@ GEM
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.10.0)
     rspec-support (3.10.2)
-    rubocop (1.12.1)
+    rubocop (1.13.0)
       parallel (~> 1.10)
       parser (>= 3.0.0.0)
       rainbow (>= 2.2.2, < 4.0)