Bump rubocop from 0.92.0 to 1.6.0

Bumps [rubocop](https://github.com/rubocop-hq/rubocop) from 0.92.0 to 1.6.0.
- [Release notes](https://github.com/rubocop-hq/rubocop/releases)
- [Changelog](https://github.com/rubocop-hq/rubocop/blob/master/CHANGELOG.md)
- [Commits](rubocop/rubocop@v0.92.0...v1.6.0)

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

Author: dependabot-preview[bot]

Gemfile.lock

@@ -209,13 +209,13 @@ GEM
       actionpack (>= 5.0)
       railties (>= 5.0)
     rexml (3.2.4)
-    rubocop (1.4.2)
+    rubocop (1.6.0)
       parallel (~> 1.10)
       parser (>= 2.7.1.5)
       rainbow (>= 2.2.2, < 4.0)
-      regexp_parser (>= 1.8)
+      regexp_parser (>= 1.8, < 3.0)
       rexml
-      rubocop-ast (>= 1.1.1)
+      rubocop-ast (>= 1.2.0, < 2.0)
       ruby-progressbar (~> 1.7)
       unicode-display_width (>= 1.4.0, < 2.0)
     rubocop-ast (1.3.0)