Missing "response-time-ms" when querying check api

**Describe the bug**
Running `curl $IP:8080/check` on a goldpinger pod some of the returned results are missing field "response-time-ms". Are values less than 1ms just missing?

**To Reproduce**
Steps to reproduce the behavior:
on a kube cluster with a sufficently low enough network latency you'll see statuc-code 200s returned but no "response-time-ms" field:

```
# curl 172.20.0.221:8080/check | python -mjson.tool
...
"podResults": {
"x.x.x.x": {
"HostIP": "x.x.x.x",
"OK": true,
"response": {
"boot_time": "2020-01-03T20:51:07.082Z"
},
"status-code": 200
},
...
```

**Expected behavior**
The field "response-time-ms" to exist when status-code 200 is returned

**Environment (please complete the following information):**
- OpenShift 3.11

Reproduce the issue with curl against the /check endpoint on a Kubernetes cluster with low network latency, using python -mjson.tool to inspect the response. Trace how the check API constructs podResults and verify that every result with status-code 200 includes response-time-ms, including values below 1ms.

Written by the indexing model from the issue text.