avoid rubygem warning on rubyzip version

Author: ianfixes

arduino_ci.gemspec

@@ -26,7 +26,7 @@ Gem::Specification.new do |spec|
   spec.require_paths = ["lib"]
 
   spec.add_dependency "os", "~> 1.0"
-  spec.add_dependency "rubyzip", "~> 1.2.1"
+  spec.add_dependency "rubyzip", "~> 1.2"
 
   spec.add_development_dependency "bundler", "~> 1.15"
   spec.add_development_dependency "rspec", "~> 3.0"