I have no clue how it worked previously in CI, but now
it's using default path to the inventory - which does
not exist.
In addition to that, type=int in cliff will default to
None, so the check had to be rewritten - because we
always did cert expiry check instead of generating them.
Change-Id: I84d71558c2666ba2cfa47054f782d25ff0c1f691