Log restart reason if runtime reports it

[raymyers]

End-user friendly description of the problem this fixes or functionality that this introduces

• Include this change in the Release Notes. If checked, you must provide an end-user friendly description for your change below

---

Give a summary of what the PR does, explaining any non-trivial design decisions

Previously, pod_status was passed from runtime-api. Recently, new fields were added to provide more detail: restart_count (number) and restart_reasons list of string. The out of memory scenario (Reason "OOM") is a motivation. This additional logging is intended to act gracefully when one or both of these fields is missing, although going forward they should be there.

---

Link of any specific issues this addresses

[tofarr]

LGTM!

[raymyers]

LGTM!

Thanks @tofarr. Feel free to mash the button at will.