Bump govuk-lint from 3.11.0 to 3.11.1

Bumps [govuk-lint](https://github.com/alphagov/govuk-lint) from 3.11.0 to 3.11.1.
- [Release notes](https://github.com/alphagov/govuk-lint/releases)
- [Changelog](https://github.com/alphagov/govuk-lint/blob/master/CHANGELOG.md)
- [Commits](alphagov/govuk-lint@v3.11.0...v3.11.1)

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

Gemfile.lock

@@ -113,7 +113,7 @@ GEM
       nokogiri (~> 1.5)
       rinku (~> 2.0)
       sanitize (~> 5)
-    govuk-lint (3.11.0)
+    govuk-lint (3.11.1)
       rubocop (~> 0.64)
       rubocop-rspec (~> 1.28)
       scss_lint
@@ -199,12 +199,11 @@ GEM
       nokogiri (~> 1.8, >= 1.8.4)
     null_logger (0.0.1)
     oj (3.7.12)
-    parallel (1.13.0)
-    parser (2.6.0.0)
+    parallel (1.17.0)
+    parser (2.6.3.0)
       ast (~> 2.4.0)
     phantomjs (2.1.1.0)
     plek (2.1.1)
-    powerpack (0.1.2)
     pry (0.12.2)
       coderay (~> 1.1.0)
       method_source (~> 0.9.0)
@@ -269,14 +268,13 @@ GEM
     rinku (2.0.6)
     robotex (1.0.0)
     rouge (3.3.0)
-    rubocop (0.64.0)
+    rubocop (0.68.1)
       jaro_winkler (~> 1.5.1)
       parallel (~> 1.10)
       parser (>= 2.5, != 2.5.1.1)
-      powerpack (~> 0.1)
       rainbow (>= 2.2.2, < 4.0)
       ruby-progressbar (~> 1.7)
-      unicode-display_width (~> 1.4.0)
+      unicode-display_width (>= 1.4.0, < 1.6)
     rubocop-rspec (1.32.0)
       rubocop (>= 0.60.0)
     ruby-progressbar (1.10.0)
@@ -331,7 +329,7 @@ GEM
     unf (0.1.4)
       unf_ext
     unf_ext (0.0.7.5)
-    unicode-display_width (1.4.1)
+    unicode-display_width (1.5.0)
     unicorn (5.4.1)
       kgio (~> 2.6)
       raindrops (~> 0.7)