sendgrid-actionmailer.gemspec in sendgrid-actionmailer-2.6.0 vs sendgrid-actionmailer.gemspec in sendgrid-actionmailer-3.0.0

@@ -17,10 +17,10 @@
   spec.files         = `git ls-files -z`.split("\x0")
   spec.executables   = spec.files.grep(%r{^bin/}) { |f| File.basename(f) }
   spec.test_files    = spec.files.grep(%r{^(test|spec|features)/})
   spec.require_paths = ['lib']
 
-  spec.add_dependency 'mail', '~> 2.5'
+  spec.add_dependency 'mail', '~> 2.7'
   spec.add_dependency 'sendgrid-ruby', '~> 6.0'
 
   spec.add_development_dependency 'appraisal', '~> 2.1.0'
   spec.add_development_dependency 'bundler'
   spec.add_development_dependency 'rake'