Update simplecov requirement from ~> 0.21.2 to ~> 0.22.0

Updates the requirements on [simplecov](https://github.com/simplecov-ruby/simplecov) to permit the latest version.
- [Release notes](https://github.com/simplecov-ruby/simplecov/releases)
- [Changelog](https://github.com/simplecov-ruby/simplecov/blob/main/CHANGELOG.md)
- [Commits](simplecov-ruby/simplecov@v0.21.2...v0.22.0)

---
updated-dependencies:
- dependency-name: simplecov
  dependency-type: direct:development
...

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

Author: dependabot[bot]

Gemfile

@@ -7,7 +7,7 @@ gemspec
 gem 'rake', require: false
 
 group :test do
-  gem 'simplecov', '~> 0.21.2'
+  gem 'simplecov', '~> 0.22.0'
   gem 'simplecov-html', '~> 0.12.3'
   gem 'simplecov-lcov', '~> 0.8.0'
   gem 'pry'