The method "getConsumerAddressNum" in ServiceCheckUtils doesn't check all registries

- [x] I have searched the [issues](https://github.com/apache/dubbo/issues) of this repository and believe that this is not a duplicate.
- [x] I have checked the [FAQ](https://github.com/apache/dubbo/blob/master/FAQ.md) of this repository and believe that this is not a duplicate.

### Environment

* Dubbo version: 2.7.12
* Operating System version: Mac OS 10.12.1
* Java version: 12.0.2

### Steps to reproduce this issue
https://github.com/apache/dubbo/blob/149d1f68e53e7809eb5e8bdde6a9d04dfbaca522/dubbo-plugin/dubbo-qos/src/main/java/org/apache/dubbo/qos/command/util/ServiceCheckUtils.java#L45-L47

As is said in the statement starting with "// TODO", when the system wants to get the number of consumer service addresses, the number obtained may be inaccurate in the case of multiple registries.
When using Qos(Quality of Service), a tool used to query and control services dynamically in Dubbo, the number will be 0 even if the consumer has some addresses.


### Expected Result

The system should be able to handle the situation of multiple registries when getting the number of consumer service addresses.