title: payment intent is null in a subscription checkout session
body: <p>I am integrating stripe using php by following this tutorial:
  <a href="https://phppot.com/php/manage-recurring-payments-using-stripe-billing-in-php/" rel="nofollow noreferrer">https://phppot.com/php/manage-recurring-payments-using-stripe-billing-in-php/</a>
  (my website has some subscription plans and redirects to the stripe checkout form ) . however, for the last step, I decided not to use webhooks, I chose to store the info like in this tutorial <a href="https://www.codexworld.com/stripe-checkout-payment-gateway-integration-php/" rel="nofollow noreferrer">https://www.codexworld.com/stripe-checkout-payment-gateway-integration-php/</a> (I know it is not for subscription but I just use the success.php code from this tutorial to collect the customer info and payment intent details).
  I tested it, gone throught the stripe checkout form , and on success I printed the checkout session object and noticed that the payment_intent field of that object is empty ! so i cannot load the payment intent object and get its info although the payment is successfully made and it is showing on the dashboard . any idea why ??</p>
  <p>EDIT :
  According to the documenttaion of a checkout session (<a href="https://stripe.com/docs/api/checkout/sessions/object" rel="nofollow noreferrer">https://stripe.com/docs/api/checkout/sessions/object</a>), the payment_intent  field stores the ID of the PaymentIntent for Checkout Sessions in payment mode. In my case I have a subscription mode not a payment one. however,if I still want to  get the $intent-&gt;status , can I use the payment_status field of the session object  $checkout_session-&gt;payment_status?
  And if subcription payments really don't have paymentintents , then why did the payment appear in the payments section on the dashboard?</p>