Stripe button styling

[hanseaston]

The styling of the button is inconsistent with the stylings of the rest of the checkout page.

We might want to change the styling to match it with the stylings of the other components. In particular, it is better to use the button component already defined in the components folder.

You might run into potential issues because the current button and the stripe credit form is bundled together (we downloaded the entire component using a stripe npm package). So you might need to come up with an alternative way of making this work. Please check out the Stripe API on ideas. You are totally welcome to reinvent the Stripe payment flow as you would wish and make it really different. The design choice is up to you!