Update rake requirement from ~> 13.0.6 to ~> 13.1.0

Updates the requirements on [rake](https://github.com/ruby/rake) to permit the latest version.
- [Release notes](https://github.com/ruby/rake/releases)
- [Changelog](https://github.com/ruby/rake/blob/master/History.rdoc)
- [Commits](ruby/rake@v13.0.6...v13.1.0)

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

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

simple_structured_logger.gemspec

@@ -19,6 +19,6 @@ Gem::Specification.new do |spec|
   spec.metadata['rubygems_mfa_required'] = 'true'
 
   spec.add_development_dependency "bundler", "~> 2.3.10"
-  spec.add_development_dependency "rake", "~> 13.0.6"
+  spec.add_development_dependency "rake", "~> 13.1.0"
   spec.add_development_dependency "minitest", "~> 5.16"
 end