As we moved to using `-detach` for registering jobs, we should wait
until allocs and deployments are created before asserting their
properties.
Fixing `TestNodeDrainIgnoreSystem` and `TestRescheduleProgressDeadlineFail` tests as they seem particularly flaky, failing 9 and 7 times (respectively) in the last two weeks.
The nodedrain deadline test asserts that all allocations are migrated by the
deadline. However, when the deadline is short (e.g. 10s), the test may fail
because of scheduler/client-propagation delays.
In one failing test, it took ~15s from the RPC call to the moment to the moment
the scheduler issued migration update, and then 3 seconds for the alloc to be
stopped.
Here, I increase the timeouts to avoid such false positives.
The E2E framework wraps testify's `require` so that by default we can stop
tests on errors, but the cleanup functions should use `assert` so that we
continue to try to cleanup the test environment even if there's a failure.
