Merge pull request #643 from agrare/add_mutex_m_to_gemspec

Add mutex_m to gemspec for ruby 3.4

Author: Fryguy

kubeclient.gemspec

@@ -24,6 +24,7 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency 'rake', '~> 13.0'
   spec.add_development_dependency 'minitest', '~> 5.15.0'
   spec.add_development_dependency 'minitest-rg'
+  spec.add_development_dependency 'mutex_m', '~> 0.3'
   spec.add_development_dependency 'webmock', '~> 3.0'
   spec.add_development_dependency 'rubocop', '~> 1.3.0' # locked to minor so new cops don't slip in
   spec.add_development_dependency 'googleauth', '~> 1.3'