SpringBoot TaskExecutorBuilder only uses second-precision when configuring the await termination period

Prior to this change, TaskExecutorBuilder used second as its precision to map awaitTerminationPeriod value. This caused a loss of millisecond information in the period. This commit fixes the loss by converting the period to millisecond and use the setAwaitTerminationMillis on executor/scheduler.

Comment From: snicoll

@wilkinsona I am not sure I'd qualify this as a bug. This feature did not exist in Spring Framework before 5.2.4, see https://github.com/spring-projects/spring-framework/pull/24496

Comment From: wilkinsona

Thanks very much, @ttddyy.