krel: fix layout used to parse GCB time
krel: fix layout used to parse GCB time

The layout we currently use doesn't work well if GCB returns time that
has less than 6 digits in seconds fraction. In such cases, it returns an
error such as:

parsing the end job time: parsing time "2021-12-15T13:25:53.713850050Z"
as "2006-01-02T15:04:05.000000Z": cannot parse "050Z" as "Z"

In this concrete case -- where we pass time returned by GCB, we want to
allow any number of digits in the seconds fraction.

Signed-off-by: Marko Mudrinić <4a0eec27869ca80b0f466641b289eb863f79126e@gmail.com>

kubernetes/release,kubernetes/release