fix ignore conditions nil error

[jakecoffman]

fixes #9457

This adds the stacktrace to the logs which allowed me to track down one of the other issues in #9457.

In job.json we started sending updated-at in the ignore conditions so it could be used for sorting, but here in the code it was used incorrectly as updated_at.

Then later when types were applied, a T.must was added which always fails because neither created_at nor created-at are ever sent in the payload.

It would be best if job.rb immediately parsed the job.json into types and passed those around instead of hashes. That would help avoid this problem in the future.

From what I can tell, updated-at should always be sent, but I was a bit defensive and set the time to the epoch for any that don't have that field set.

[jakecoffman]

Looks like #7787 fixed the updated_at issue but then it got unfixed again.

[jakecoffman]

The tests in #7787 were ineffective as it used the wrong key updated_at but also it was asserting the natural sort order. So once I fixed the key the test still passed.

By making business4 nil I'm able to test both the fallback logic and the key itself.

[JamieMagee]

I still don't have my permissions back, so I can't approve this PR, but LGTM