void markShadowBucketAsDestroyed(String shadowBucketPath) {
    destroyedShadowBuckets.put(shadowBucketPath, true);
  }
Returns the runnable used to consume the volunteering queue. The executing thread(s) will
consume from the queue until it is empty.

@return runnable for consuming the volunteering queue
geode-core/src/main/java/org/apache/geode/internal/cache/BucketAdvisor.java