Retrieve product variants

curl --request GET \
  --url https://staging.api.commercengine.io/api/v1/{store_id}/storefront/catalog/products/{product_id}/variants \
  --header 'Authorization: Bearer <token>'

{
  "message": "Products retrieved successfully.",
  "success": true,
  "content": {
    "variants": [
      {
        "id": "<string>",
        "product_id": "<string>",
        "sku": "<string>",
        "slug": "<string>",
        "name": "<string>",
        "product_name": "<string>",
        "short_description": "<string>",
        "active": true,
        "stock_available": true,
        "backorder": true,
        "on_offer": true,
        "on_promotion": true,
        "on_subscription": true,
        "is_default": true,
        "associated_options": {
          "background_color": {
            "name": "Background Color",
            "value": {
              "name": "Blue",
              "hexcode": "#0000FF"
            },
            "type": "color"
          },
          "size": {
            "name": "Size",
            "value": "Large",
            "type": "single-select"
          }
        },
        "images": [
          {
            "id": "<string>",
            "title": "<string>",
            "alternate_text": "<string>",
            "sort_order": 123,
            "url_tiny": "<string>",
            "url_thumbnail": "<string>",
            "url_standard": "<string>",
            "url_zoom": "<string>"
          }
        ],
        "pricing": {
          "currency": "<string>",
          "tax_type": "GST",
          "tax_rate": 123,
          "price_including_tax": false,
          "listing_price": 123,
          "selling_price": 123,
          "min_order_quantity": 1,
          "max_order_quantity": 123,
          "incremental_quantity": 1,
          "selling_price_excluding_tax": 123
        },
        "subscription": [
          {
            "id": "<string>",
            "subscription_plan": "<string>",
            "subscription_price": 123,
            "billing_interval": 123,
            "billing_frequency": "monthly",
            "billing_limit": 123,
            "fulfill_separately": false,
            "order_interval": 123,
            "order_frequency": "monthly",
            "order_limit": 123,
            "minimum_quantity": 123,
            "billing_trial_days": 123
          }
        ],
        "promotion": {
          "id": "<string>",
          "starts_at": "2023-11-07T05:31:56Z",
          "expires_at": "2023-11-07T05:31:56Z",
          "details": {
            "promotion_type": "discount",
            "discount_type": "percentage",
            "discount_percent": 123,
            "discount_fixed_amount": 123
          }
        }
      }
    ]
  }
}