asciidoctor-epub3.gemspec in asciidoctor-epub3-1.5.0.alpha.15 vs asciidoctor-epub3.gemspec in asciidoctor-epub3-1.5.0.alpha.16

@@ -34,11 +34,12 @@
   s.add_development_dependency 'coderay', '~> 1.1.0'
   s.add_development_dependency 'pygments.rb', '~> 1.2.0'
   s.add_development_dependency 'rake', '~> 13.0.0'
   s.add_development_dependency 'rouge', '~> 3.0'
   s.add_development_dependency 'rspec', '~> 3.9.0'
-  s.add_development_dependency 'rubocop', '~> 0.80.0'
+  s.add_development_dependency 'rubocop', '~> 0.81.0'
   s.add_development_dependency 'rubocop-rspec', '~> 1.38.0'
 
   s.add_runtime_dependency 'asciidoctor', '>= 1.5.6', '< 3.0.0'
   s.add_runtime_dependency 'gepub', '~> 1.0.0'
+  s.add_runtime_dependency 'mime-types', '~> 3.0'
 end