fix: handled duplicate key in SecurityAuditDestination

[Hardikl]

Tried with these records,

{
    "records": [
        {
            "address": "x.x.x.x",
            "port": 6414,
            "ipspace": {
                "name": "Default",
                "uuid": "d192470e-0580-11e8-bd9d-00a098d39e12"
            },
            "protocol": "tcp_encrypted",
            "facility": "user",
            "verify_server": true,
            "message_format": "legacy_netapp",
            "timestamp_format_override": "no_override",
            "hostname_format_override": "no_override",
            "_links": {
                "self": {
                    "href": "/api/security/audit/destinations/x.x.x.x/6414"
                }
            }
        },
        {
            "address": "x.x.x.x",
            "port": 6514,
            "ipspace": {
                "name": "Default",
                "uuid": "d192470e-0580-11e8-bd9d-00a098d39e12"
            },
            "protocol": "tcp_encrypted",
            "facility": "user",
            "verify_server": true,
            "message_format": "legacy_netapp",
            "timestamp_format_override": "no_override",
            "hostname_format_override": "no_override",
            "_links": {
                "self": {
                    "href": "/api/security/audit/destinations/x.x.x.x/6514"
                }
            }
        }
    ],
    "num_records": 2,
    "_links": {
        "self": {
            "href": "/api/security/audit/destinations?fields=*"
        }
    }
}