Bump simplecov from 0.20.0 to 0.21.0 (#15485)

Bumps [simplecov](https://github.com/simplecov-ruby/simplecov) from 0.20.0 to 0.21.0.
- [Release notes](https://github.com/simplecov-ruby/simplecov/releases)
- [Changelog](https://github.com/simplecov-ruby/simplecov/blob/main/CHANGELOG.md)
- [Commits](https://github.com/simplecov-ruby/simplecov/compare/v0.20.0...v0.21.0)

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Gemfile

@@ -123,7 +123,7 @@ group :test do
   gem 'microformats', '~> 4.2'
   gem 'rails-controller-testing', '~> 1.0'
   gem 'rspec-sidekiq', '~> 3.1'
-  gem 'simplecov', '~> 0.20', require: false
+  gem 'simplecov', '~> 0.21', require: false
   gem 'webmock', '~> 3.11'
   gem 'parallel_tests', '~> 3.4'
   gem 'rspec_junit_formatter', '~> 0.4'

Gemfile.lock

@@ -184,7 +184,7 @@ GEM
     diff-lcs (1.4.4)
     discard (1.2.0)
       activerecord (>= 4.2, < 7)
-    docile (1.3.2)
+    docile (1.3.4)
     domain_name (0.5.20190701)
       unf (>= 0.0.5, < 1.0.0)
     doorkeeper (5.4.0)
@@ -589,7 +589,7 @@ GEM
     simple_form (5.0.3)
       actionpack (>= 5.0)
       activemodel (>= 5.0)
-    simplecov (0.20.0)
+    simplecov (0.21.0)
       docile (~> 1.1)
       simplecov-html (~> 0.11)
       simplecov_json_formatter (~> 0.1)
@@ -795,7 +795,7 @@ DEPENDENCIES
   sidekiq-unique-jobs (~> 6.0)
   simple-navigation (~> 4.1)
   simple_form (~> 5.0)
-  simplecov (~> 0.20)
+  simplecov (~> 0.21)
   sprockets (~> 3.7.2)
   sprockets-rails (~> 3.2)
   stackprof