[FIXED JENKINS-28690] Deadlock in hudson.model.Executor

- Rather fun one here. The Lock code relies on assuming that Thread.interrupted() is clear on entry
- If it then sees Thread.interrupted() set, it will interrupt the current thread in order to set the
  flag again.
- Executor is a thread that does funky things with an overridden interrupt method
- Executor.abortResult() is used to track a build be interrupted or aborted in some other way
- As a result the abortResult can cause a deadlockif there is a genuine interruption
- This fix clears the interrupt flag in abortResult() and uses the write lock in order to ensure:
    - The same lock as used in interrupt() is helf
    - The interrupt flag is clear
- Clearing the interrupt flag should be safe as the only time it is called is immediately after
  an interruption and the resulting exception is caught and rethrown/logged anyway