Retrieve all subscriptions

curl --request GET \
  --url https://services.commercengine.dev/api/v1/x2yh61zw4k/admin/subscriptions \
  --header 'Authorization: Bearer <token>'

{
  "message": "<string>",
  "success": true,
  "content": {
    "subscriptions": [
      {
        "id": "<string>",
        "subscription_number": "<string>",
        "name": "<string>",
        "sub_total": 123,
        "shipping_amount": 123,
        "total_tax": 123,
        "net_amount": 123,
        "billing_frequency": "Monthly",
        "billing_interval": 1,
        "billing_limit": 0,
        "fulfill_separately": true,
        "fulfillment_frequency": "Monthly",
        "fulfillment_interval": 1,
        "fulfillment_limit": 0,
        "billing_trial_days": 0,
        "status": "draft",
        "created_at": "2023-11-07T05:31:56Z",
        "modified_at": "2023-11-07T05:31:56Z"
      }
    ]
  }
}