The E2E test suite for rescheduling had a few bugs:
* Using the command line to stop a job with a failing deployment returns a non-zero exit
code, which would cause an otherwise passing test to fail.
* Two of the input jobs were actually invalid but were only correctly detected
as such because of #17342
This changeset also updates the whole test suite to move it off the v1
"framework". A few test assertions are also de-flaked.
Fixes: #19076
