Gets users with the associated external ids

Example response

[
  {
    "_links": [
      {
        "href": "https://an.example.link",
        "method": "GET",
        "rel": "self"
      }
    ],
    "email": "user@somegovernmentdept.gov.uk",
    "external_id": "93ba1ec4ed6a4238a59f16ad97b4fa12",
    "features": "feature1, feature2",
    "last_logged_in_at": "2022-04-06T23:03:41.665Z",
    "otp_key": "43c3c4t",
    "provisional_otp_key": "FC5IHFH2CFSKEZBBXTYEGQXQOH344LLO",
    "second_factor": "SMS",
    "service_roles": [
      {
        "role": {
          "description": "Administrator",
          "name": "admin",
          "permissions": [
            {
              "description": "Revokekey",
              "name": "tokens:delete"
            }
          ]
        },
        "service": {
          "_links": [
            {
              "href": "https://an.example.link",
              "method": "GET",
              "rel": "self"
            }
          ],
          "archived_date": "2023-04-09T18:07:46.568Z",
          "collect_billing_address": true,
          "created_date": "2022-04-01T12:07:46.568Z",
          "current_go_live_stage": "NOT_STARTED",
          "current_psp_test_account_stage": "NOT_STARTED",
          "custom_branding": {
            "css_url": "css url",
            "image_url": "image url"
          },
          "default_billing_address_country": "GB",
          "external_id": "7d19aff33f8948deb97ed16b2912dcd3",
          "gateway_account_ids": [
            "1"
          ],
          "merchant_details": {
            "address_city": "London",
            "address_country": "GB",
            "address_line1": "Address line 1",
            "address_line2": "Address line 2",
            "address_postcode": "E1 8XX",
            "email": "email@example.com",
            "name": "organisation name",
            "telephone_number": "447700900000",
            "url": "http://www.example.org"
          },
          "name": "Some service name",
          "sector": "local government",
          "service_features": {
            "test_feature": {
              "enabled": true
            },
            "test_feature_2": {
              "enabled": false
            }
          },
          "service_name": {
            "cy": "Service name in welsh",
            "en": "Some service name"
          },
          "went_live_date": "2022-04-09T18:07:46.568Z"
        }
      }
    ],
    "telephone_number": "447700900000"
  }
]