What are the $1 entries in the Payments section on Stripe?

Do not be alarmed. This is simply a process to verify that a new card is in good standing. There is no money being charged to the card, but it will show up on your Stripe Payment History as a "Canceled" $1 transaction. You can simply ignore these entries, they are designed as an extra safety measure. 

Here's how it works: In order to ensure that the credit card information you receive with an order is for a credit card that is in good standing, a verification process must take place with the payment gateway. This is accomplished behind the scenes by performing an authorize against the card for the minimum amount that the gateway will allow ($1) and then immediately voiding the authorization. If the authorize succeeds you know the card is in good standing. And you're all set!