bug: new ndt-client json output

[ggmartins]

old:

{
    "ServerFQDN": "ndt-mlab3-ord03.mlab-oti.measurement-lab.org",
    "ServerIP": "[REDACTED]",
    "ClientIP": "[REDACTED]",
    "DownloadUUID": "ndt-j6ld9_1673569719_00000000002493B8",
    "Download": {
        "Value": 204.9798363221392,
        "Unit": "Mbit/s"
    },
    "Upload": {
        "Value": 139.31888132755253,
        "Unit": "Mbit/s"
    },

new:

 {
    "ServerFQDN": "ndt-mlab3-ord04.mlab-oti.measurement-lab.org",
    "ServerIP": "[REDACTED]",
    "ClientIP": "[REDACTED]",
    "Download": {
        "UUID": "ndt-lp5bb_1673588518_000000000020DD9D",
        "Throughput": {
            "Value": 905.9671880820414,
            "Unit": "Mbit/s"
        },
        "Latency": {
            "Value": 4.096,
            "Unit": "ms"
        },

I'd also add ndt_latency as part of the metrics we want to record (from Latency).

[fathimamaha]

commit hash: b07bd5f8caef264c11f49d9f24272fcd5bb6dcb5

new json does not have min rtt, for now I have commented the code out, Example:

{
  'ServerFQDN': 'ndt-mlab1-ord03.mlab-oti.measurement-lab.org',
  'ServerIP': '2001:5a0:4200::75',
  'ClientIP': '2601:240:cf82:2fe0::baaf',
  'Download': {
    'UUID': 'ndt-f6w78_1673784969_000000000021216B',
    'Throughput': {
      'Value': 903.2970761116662,
      'Unit': 'Mbit/s'
    },
    'Latency': {
      'Value': 4.125,
      'Unit': 'ms'
    },
    'Retransmission': {
      'Value': 0,
      'Unit': '%'
    }
  },
  'Upload': {
    'UUID': 'ndt-f6w78_1673784969_00000000001FDBCE',
    'Throughput': {
      'Value': 40.88370290283756,
      'Unit': 'Mbit/s'
    },
    'Latency': {
      'Value': 3.77,
      'Unit': 'ms'
    },
    'Retransmission': {
      'Value': 0,
      'Unit': ''
    }
  }
}

[marcwitasee]

We need to deploy the new version with @fathimamaha. So far we have tested on three devices, but we need to deploy more broadly.