fix: Nokogiri::XML::XPath is a Module

It has been acting as a module since v1.0.0 (8c87f06).

Author: flavorjones

lib/nokogiri/xml/xpath.rb

@@ -3,9 +3,7 @@
 
 module Nokogiri
   module XML
-    class XPath
-      # The Nokogiri::XML::Document tied to this XPath instance
-      attr_accessor :document
+    module XPath
     end
   end
 end

lib/nokogiri/xml/xpath/syntax_error.rb

@@ -1,7 +1,7 @@
 # frozen_string_literal: true
 module Nokogiri
   module XML
-    class XPath
+    module XPath
       class SyntaxError < XML::SyntaxError
         def to_s
           [super.chomp, str1].compact.join(': ')