static ScheduledExecutorService makeContextPropagating(ScheduledExecutorService executor) {
        return PropagatingContextAwareScheduledExecutorService.of(executor);
    }
Returns a {@link ScheduledExecutorService} that will execute callbacks in the given {@code executor},
propagating the caller's {@link RequestContext} (if any) into the callback execution.
If this executor service is only used from a single request then it's better to use
{@link #makeContextAware(ScheduledExecutorService)}
core/src/main/java/com/linecorp/armeria/common/RequestContext.java