Unnecessary creation of Stripe "payment intent"

[nick4501]

Describe the bug
When using the Stripe payment method, a payment intent is automatically created as soon as the customer starts the checkout process - even if the customer decides to use another payment method instead. This results in lots of incomplete payments being added to the Stripe payment portal, which seems unnecessary.

To Reproduce
Steps to reproduce the behavior:

1. Ensure that multiple payment methods are possible (e.g. Stripe and Paypal) and that Stripe is the first payment method in the list.
2. Add a product to a basket and go through the checkout process.
3. On the payment method selection page, select Paypal and continue with the checkout process.
4. A Stripe payment intent will have been created, resulting in an "INCOMPLETE PAYMENT" in the Stripe administration dashboard. This should not be created at all, as the customer checked out using Paypal.

Expected behavior
A payment intent should only be raised on the Stripe portal when the user starts to fill in their card details. If the Stripe payment method is the first in a list of possible payment methods, then it will automatically select it and start the creation of the Stripe payment intent. This is unnecessary and floods the Stripe dashboard payment list with incomplete orders.