Fix Regexp.new deprecated third argument usage (#2)

At least since ruby 2.7, passing 'n' code option to the third
argument of Regexp.new is the same as specifying
Regexp::NOENCODING to the second argument.

Now with ruby 3.2, using third argument is declared deprecated,
and with ruby 3.3, third argument support is removed:
ruby/ruby#7039

To handle ruby 3.3, fix Regexp.new usage as above.

Author: mtasaka

lib/cookiejar/cookie_validation.rb

@@ -45,7 +45,7 @@ module PATTERN
     HDN = /\A#{PATTERN::HOSTNAME}\Z/
     TOKEN = /\A#{PATTERN::TOKEN}\Z/
     PARAM1 = /\A(#{PATTERN::TOKEN})(?:=#{PATTERN::VALUE1})?\Z/
-    PARAM2 = Regexp.new "(#{PATTERN::TOKEN})(?:=(#{PATTERN::VALUE2}))?(?:\\Z|;)", '', 'n'
+    PARAM2 = Regexp.new "(#{PATTERN::TOKEN})(?:=(#{PATTERN::VALUE2}))?(?:\\Z|;)", Regexp::NOENCODING
     # TWO_DOT_DOMAINS = /\A\.(com|edu|net|mil|gov|int|org)\Z/
 
     # Converts the input object to a URI (if not already a URI)