Spec documentation: Address should be singular

lib/cocoapods/command/spec.rb

@@ -493,7 +493,7 @@ Pod::Spec.new do |s|
   #
   #  Specify the authors of the library, with email addresses. Email addresses
   #  of the authors are extracted from the SCM log. E.g. $ git log. CocoaPods also
-  #  accepts just a name if you'd rather not provide an email addresses.
+  #  accepts just a name if you'd rather not provide an email address.
   #
   #  Specify a social_media_url where others can refer to, for example a twitter
   #  profile URL.