fix(payment): STRIPE-426 fix gpay shipping for buy now flow

[PavlenkoM]

What?

Fix GPay shipping address and shipping options for digital products. Change GPay widget initialisation process.

Why?

We should not show Shipping address and shipping options for digital products.

Testing / Proof

Stripe

PDP:

Physical product:

https://github.com/user-attachments/assets/47c64a32-ab70-4376-998d-e3b5e5260fd9

Digital:

https://github.com/user-attachments/assets/84177b37-2b08-4d36-9b24-002f94d54de9

Cart page:

Physical

https://github.com/user-attachments/assets/97085fce-32b6-4675-b84b-8b5bc55a0722

Digital

https://github.com/user-attachments/assets/3b3e7681-8903-43e7-b853-00ca5006750e

Checkout page

Physical

https://github.com/user-attachments/assets/ed534e6e-a3e0-419e-8143-b61b3192a4ee

Digital

https://github.com/user-attachments/assets/9bef66d9-81dd-4aa8-b6a1-c8b8a18772c1

Physical

https://github.com/user-attachments/assets/21352187-ce57-4ed6-938f-f12a9d44f514

Digital

https://github.com/user-attachments/assets/202e566f-039e-488a-bf8b-446839428ae5

PayPal

PDP

Physical

https://github.com/user-attachments/assets/b689c34d-4f1a-4202-a7c3-2c92883b27b5

Digital

https://github.com/user-attachments/assets/82ad0fb0-b761-4f36-addd-9be4d6dc6c2d

Cart page

Physical

https://github.com/user-attachments/assets/bbb591e3-3c5a-4922-ae19-bdde9972595e

Digital

https://github.com/user-attachments/assets/95650975-f927-4ee3-bc82-c8aa5dff29ae

Checkout page

Physical

https://github.com/user-attachments/assets/cdc7d786-f77a-4b12-ba72-97ffa5b33ec4

Digital

https://github.com/user-attachments/assets/63ec47aa-e16e-49ad-8970-703a389fa853

Physical

https://github.com/user-attachments/assets/97e7449b-6aa9-403b-888a-202a92234cf0

Digital

https://github.com/user-attachments/assets/2514b5c8-d1ce-46f7-9b2b-4b2254f41b73

Unit tests coverage

@bigcommerce/team-checkout @bigcommerce/team-payments