users.template.json

{
    "$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json#",
    "contentVersion": "1.0.0.0",
    "parameters": {
        "ApimServiceName": {
          "type": "string"
        }
    },
    "resources": [
        {
            "type": "Microsoft.ApiManagement/service/users",
            "name": "[concat(parameters('ApimServiceName'), '/john-doe-contoso-com')]",
            "apiVersion": "2018-01-01",
            "scale": null,
            "properties": {
                "firstName": "John",
                "lastName": "Doe",
                "email": "john.doe@contoso.com",
                "state": "active",
                "note": "Internal consumer of our APIs",
                "confirmation": "invite"
            }
        }
    ]
  }