Merge pull request #522 from zipmark/dependabot/bundler/gherkin-tw-9.0.0

Update gherkin requirement from ~> 3.2.0 to ~> 9.0.0 [ci skip]

Author: bf4

rspec_api_documentation.gemspec

@@ -34,7 +34,7 @@ Gem::Specification.new do |s|
   s.add_development_dependency "inch", "~> 0.8.0"
   s.add_development_dependency "minitest", "~> 5.8.4"
   s.add_development_dependency "contracts", "~> 0.17"
-  s.add_development_dependency "gherkin", "~> 3.2.0"
+  s.add_development_dependency "gherkin", "~> 9.0.0"
   s.add_development_dependency "multi_json", "~> 1.15.0"
   s.add_development_dependency "rspec", "~> 3.0"