Bump simplecov from 0.17.1 to 0.18.1 (#13027)

Bumps [simplecov](https://github.com/colszowka/simplecov) from 0.17.1 to 0.18.1.
- [Release notes](https://github.com/colszowka/simplecov/releases)
- [Changelog](https://github.com/colszowka/simplecov/blob/master/CHANGELOG.md)
- [Commits](https://github.com/colszowka/simplecov/compare/v0.17.1...v0.18.1)

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

Gemfile

@@ -124,7 +124,7 @@ group :test do
   gem 'microformats', '~> 4.2'
   gem 'rails-controller-testing', '~> 1.0'
   gem 'rspec-sidekiq', '~> 3.0'
-  gem 'simplecov', '~> 0.17', require: false
+  gem 'simplecov', '~> 0.18', require: false
   gem 'webmock', '~> 3.8'
   gem 'parallel_tests', '~> 2.30'
 end

Gemfile.lock

@@ -584,11 +584,10 @@ GEM
     simple_form (5.0.1)
       actionpack (>= 5.0)
       activemodel (>= 5.0)
-    simplecov (0.17.1)
+    simplecov (0.18.1)
       docile (~> 1.1)
-      json (>= 1.8, < 3)
+      simplecov-html (~> 0.11.0)
-      simplecov-html (~> 0.10.0)
+    simplecov-html (0.11.0)
-    simplecov-html (0.10.2)
     sprockets (3.7.2)
       concurrent-ruby (~> 1.0)
       rack (> 1, < 3)
@@ -773,7 +772,7 @@ DEPENDENCIES
   sidekiq-unique-jobs (~> 6.0)
   simple-navigation (~> 4.1)
   simple_form (~> 5.0)
-  simplecov (~> 0.17)
+  simplecov (~> 0.18)
   sprockets (~> 3.7.2)
   sprockets-rails (~> 3.2)
   stackprof