Update rubocop-rake requirement from = 0.5.1 to = 0.6.0

Updates the requirements on [rubocop-rake](https://github.com/rubocop/rubocop-rake) to permit the latest version.
- [Release notes](https://github.com/rubocop/rubocop-rake/releases)
- [Changelog](https://github.com/rubocop/rubocop-rake/blob/master/CHANGELOG.md)
- [Commits](rubocop/rubocop-rake@v0.5.1...v0.6.0)

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

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

lazylead.gemspec

@@ -93,7 +93,7 @@ tasks instead of solving technical problems."
   s.add_development_dependency "rubocop", "1.18.2"
   s.add_development_dependency "rubocop-minitest", "0.13.0"
   s.add_development_dependency "rubocop-performance", "1.11.3"
-  s.add_development_dependency "rubocop-rake", "0.5.1"
+  s.add_development_dependency "rubocop-rake", "0.6.0"
   s.add_development_dependency "rubocop-rspec", "2.3.0"
   s.add_development_dependency "sqlint", "0.2.0"
   s.add_development_dependency "tempfile", "0.1.1"