Bump rubocop from 0.79.0 to 0.80.0

Bumps [rubocop](https://github.com/rubocop-hq/rubocop) from 0.79.0 to 0.80.0.
- [Release notes](https://github.com/rubocop-hq/rubocop/releases)
- [Changelog](https://github.com/rubocop-hq/rubocop/blob/master/CHANGELOG.md)
- [Commits](rubocop/rubocop@v0.79.0...v0.80.0)

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

Gemfile.lock

@@ -68,6 +68,7 @@ GEM
     rainbow (3.0.0)
     rake (13.0.1)
     redis (4.1.3)
+    rexml (3.2.4)
     rollbar (2.24.0)
     rspec (3.9.0)
       rspec-core (~> 3.9.0)
@@ -85,11 +86,12 @@ GEM
       power_assert (~> 1.1.0)
       rspec (>= 2.14)
     rspec-support (3.9.2)
-    rubocop (0.79.0)
+    rubocop (0.80.0)
       jaro_winkler (~> 1.5.1)
       parallel (~> 1.10)
       parser (>= 2.7.0.1)
       rainbow (>= 2.2.2, < 4.0)
+      rexml
       ruby-progressbar (~> 1.7)
       unicode-display_width (>= 1.4.0, < 1.7)
     rubocop-performance (1.5.2)