[Dubbo-2545] 修复注册中心域名解析导致的单点问题

[356082462]

What is the purpose of the change

修复注册中心域名解析导致的单点问题，参考：#2545
修复由于域名解析成同一个注册中心的不通IP导致创建多个Registry对象的问题。

Brief changelog

将如下代码：
https://github.com/apache/incubator-dubbo/blob/e6b0bc8a856abd7f2d7a2e0f06ccc78dc90e2e0a/dubbo-registry/dubbo-registry-api/src/main/java/org/apache/dubbo/registry/support/AbstractRegistryFactory.java#L88
改为：
https://github.com/apache/incubator-dubbo/blob/7a48fac84b14ac6a21c1bdfc5958705dd8dda84d/dubbo-compatible/src/main/java/com/alibaba/dubbo/common/URL.java#L498-L500

Verifying this change

org.apache.dubbo.registry.supportAbstractRegistryFactory

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