public static <T extends Executor> boolean isTtlWrapper(@Nullable T executor) {
        return executor instanceof TtlWrapper;
    }
check the executor is a TTL executor wrapper or not.
<p>
if the parameter executor is TTL wrapper, return {@code true}, otherwise {@code false}.
<p>
NOTE: if input executor is {@code null}, return {@code false}.

@param executor input executor
@param <T>      Executor type
@see #getTtlExecutor(Executor)
@see #getTtlExecutorService(ExecutorService)
@see #getTtlScheduledExecutorService(ScheduledExecutorService)
@see #unwrap(Executor)
@since 2.8.0
ttl2-compatible/src/main/java/com/alibaba/ttl/threadpool/TtlExecutors.java