cookie_hash.rb cleanup (#687)

lib/httparty/cookie_hash.rb

@@ -1,14 +1,14 @@
 class HTTParty::CookieHash < Hash #:nodoc:
   CLIENT_COOKIES = %w(path expires domain path secure httponly samesite)
 
-  def add_cookies(value)
-    case value
+  def add_cookies(data)
+    case data
     when Hash
-      merge!(value)
+      merge!(data)
     when String
-      value.split('; ').each do |cookie|
-        array = cookie.split('=', 2)
-        self[array[0].to_sym] = array[1] if array[0]
+      data.split('; ').each do |cookie|
+        key, value = cookie.split('=', 2)
+        self[key.to_sym] = value if key
       end
     else
       raise "add_cookies only takes a Hash or a String"