make sure Jcache will exceed expired period

Author: qinnnyul

dubbo-filter/dubbo-filter-cache/src/test/java/com/alibaba/dubbo/cache/support/jcache/JCacheFactoryTest.java

@@ -43,6 +43,7 @@ public void testJCacheGetExpired() throws Exception {
         Invocation invocation = new RpcInvocation();
         Cache cache = cacheFactory.getCache(url, invocation);
         cache.put("testKey", "testValue");
+        Thread.sleep(10);
         assertNull(cache.get("testKey"));
     }