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.
