Is your feature request related to a problem? Please describe.
The annotation ApolloConfigChangeListener takes an array of string (values = String []), which means if I have some namespaces defined in an application.yaml as comma separated values, I can't inject it as it needs to be constant.

Describe the solution you'd like
Either of the two solutions are fine

1. Allow spring expression evaluation. eg - @ApolloConfigChangeListener("#{'${prop.apollo.namespaces:}'.split(',')}")
2. Provide an optional argument. eg - @ApolloConfigChangeListener(namespaces = "${prop.apollo.namespaces}")

Here my application.yaml would be

prop:
  apollo:
    namespaces: "foo,bar,other-namespace"

PS - I can share a sample PR if I can have permission on this repo.