Domains: Update GSuiteUpgrade to use useShoppingCart

[sirbrillig]

Changes proposed in this Pull Request

This updates GSuiteUpgrade to use useShoppingCart from @automattic/shopping-cart in place of CartData. This will help us eventually remove CartData (see #24019). This is similar to the upgrade to GSuiteNudge from #48438.

Depends on #48202 because otherwise the domain that was added by the domain search page will not have finished updating the cart by the time we hit the G Suite page, causing the G Suite submission to overwrite it (which will probably fail since it will be in a cart without a domain).

Testing instructions

• Add a domain to your cart.
• Verify that you see the G Suite upsell before you reach checkout.
• Add a G Suite product to your cart from the upsell.
• Verify that you arrive at checkout and that the cart contains both your domain and the G Suite product.

[matticbot]

Test live: https://calypso.live/?branch=update/gsuite-upgrade-to-use-shopping-cart

[matticbot]

Here is how your PR affects size of JS and CSS bundles shipped to the user's browser:

Sections (~95 bytes added 📈 [gzipped])

name     parsed_size           gzip_size
domains       +260 B  (+0.0%)      +95 B  (+0.0%)

Sections contain code specific for a given set of routes. Is downloaded and parsed only when a particular route is navigated to.

Legend

What is parsed and gzip size?

Parsed Size: Uncompressed size of the JS and CSS files. This much code needs to be parsed and stored in memory.
Gzip Size: Compressed size of the JS and CSS files. This much data needs to be downloaded over network.

Generated by performance advisor bot at iscalypsofastyet.com.

[sirbrillig]

Because this is so tightly tied to the domain search page, I cherry-picked this PR into #48202 and I'll close this one.