tab: correctly handle options request.

Because a `Tab` is an `OpenStruct` the existing calls to
`any_args_or_options?` would always return `false`. This means that
`Formula#declared_runtime_dependencies` would never call
`Tab#without?` to check whether a dependency has been brought in by an
option.

Fixes #4407

Library/Homebrew/tab.rb

@@ -211,6 +211,10 @@ class Tab < OpenStruct
     end
   end
 
+  def any_args_or_options?
+    !used_options.empty? || !unused_options.empty?
+  end
+
   def with?(val)
     option_names = val.respond_to?(:option_names) ? val.option_names : [val]