public void removeByKey(final String key) {
        UPSTREAM_MAP.remove(key);
        task.triggerRemoveAll(key);
    }
@Test
    @Order(3)
    public void removeByKeyTest() {
        final UpstreamCacheManager upstreamCacheManager = UpstreamCacheManager.getInstance();
        upstreamCacheManager.removeByKey(SELECTOR_ID);
    }