Handle Shopify API errors better

[sshane]

If a Shopify query returns a error status, this is what we see:

Because we try to access response when it isn't defined in the case of errors:

website/src/routes/shop/[product]/+page.js

Lines 37 to 39 in ccfce93

	throw error(response.status, {
	message: `Product ${productId} not found`,
	})