apollo-biz/src/main/java/com/ctrip/framework/apollo/biz/grayReleaseRule/GrayReleaseRulesHolder.java/GrayReleaseRulesHolder/removeCache
class GrayReleaseRulesHolder:  private void removeCache(String key, GrayReleaseRuleCache ruleCache) {
    grayReleaseRuleCache.remove(key, ruleCache);
    for (GrayReleaseRuleItemDTO ruleItemDTO : ruleCache.getRuleItems()) {
      for (String clientIp : ruleItemDTO.getClientIpList()) {
        reversedGrayReleaseRuleCache.remove(assembleReversedGrayReleaseRuleKey(ruleItemDTO
            .getClientAppId(), ruleCache.getNamespaceName(), clientIp), ruleCache.getRuleId());
      }
    }
  }