Update rdoc requirement from = 6.5.0 to = 6.6.1

Updates the requirements on [rdoc](https://github.com/ruby/rdoc) to permit the latest version.
- [Release notes](https://github.com/ruby/rdoc/releases)
- [Changelog](https://github.com/ruby/rdoc/blob/master/History.rdoc)
- [Commits](ruby/rdoc@v6.5.0...v6.6.1)

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

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

lazylead.gemspec

@@ -87,7 +87,7 @@ tasks instead of solving technical problems."
   s.add_development_dependency "minitest-reporters", "1.6.1"
   s.add_development_dependency "net-ping", "2.0.8"
   s.add_development_dependency "rake", "13.0.6"
-  s.add_development_dependency "rdoc", "6.5.0"
+  s.add_development_dependency "rdoc", "6.6.1"
   s.add_development_dependency "rubocop", "1.50.2"
   s.add_development_dependency "rubocop-minitest", "0.30.0"
   s.add_development_dependency "rubocop-performance", "1.17.1"