Termination policy that times out after a fixed period. Allows graceful exit
from a batch if the latest result comes in after the timeout expires (i.e.
does not throw a timeout exception).
N.B. It may often be the case that the batch governed by this policy will be
transactional, and the transaction might have its own timeout. In this case
the transaction might throw a timeout exception on commit if its timeout
threshold is lower than the termination policy.
Default timeout value in millisecs (the value equivalent to 30 seconds).
Check the timeout and complete gracefully if it has expires.
Start the clock on the timeout.