List Onchain Address Groups

curl --request GET \
  --url https://api.prime.coinbase.com/v1/portfolios/{portfolio_id}/onchain_address_groups

{
  "address_groups": [
    {
      "id": "<string>",
      "name": "<string>",
      "network_type": "NETWORK_TYPE_UNSPECIFIED",
      "addresses": [
        {
          "name": "<string>",
          "address": "<string>",
          "chain_ids": [
            "<string>"
          ]
        }
      ],
      "added_at": "2023-11-07T05:31:56Z"
    }
  ]
}