Checkout.md in conekta-6.0.1

- old
+ new

@@ -20,13 +20,13 @@
 
 ```ruby
 require 'conekta'
 
 instance = Conekta::Checkout.new(
-  allowed_payment_methods: [cash, card, bank_transfer],
+  allowed_payment_methods: [&quot;cash&quot;,&quot;card&quot;,&quot;bank_transfer&quot;],
   expires_at: 1680397724,
   monthly_installments_enabled: true,
-  monthly_installments_options: [3, 6, 12],
+  monthly_installments_options: [3,6,12],
   name: Payment Link Name 1594138857,
   needs_shipping_contact: false,
   on_demand_enabled: true,
   order_template: null,
   payments_limit_count: 5,