[Nacos 3.0] The namespace of ConfigChangeNotifyRequest mismatch with client when client namespace is empty

[Sunrisea]

Describe the bug
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Due to the transformation of the empty and "public" namespaces on the server side, when the client's namespace is empty, the namespace in the ConfigChangeNotifyRequest does not match the client's namespace. As a result, the client is unable to receive configuration change notifications.

Expected behavior
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Actually behavior
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How to Reproduce
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4. See errors

Desktop (please complete the following information):

• OS: [e.g. Centos]
• Version [e.g. nacos-server 1.3.1, nacos-client 1.3.1]
• Module [e.g. naming/config]
• SDK [e.g. original, spring-cloud-alibaba-nacos, dubbo]

Additional context
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