BuyNowButton @shopify/hydrogen-react should allow sellingPlanId

[edoardolunardi]

What is the location of your example repository?

None

Which package or tool is having this issue?

hydrogen-react

What version of that package or tool are you using?

2023.10.0

What version of Remix are you using?

None

Steps to Reproduce

BuyNowButton doesn't allow sellingPlanId prop.

Expected Behavior

I would expect the BuyNowButton to receive a sellingPlanId prop, along with the usual variantId. This would allow to add a subscription to the cart + redirect to checkout without extra custom logic.

Actual Behavior

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