[Bug][http-client-java] azure-json serialization, constant property in parent class cannot be accessed from child class

### Describe the bug

unbranded generated code: https://github.com/joseharriaga/openai-in-typespec/commit/25c0126d909b43c8ce6971d905f7551e6e8110ff

tsp source: https://github.com/joseharriaga/openai-in-typespec/blob/610b77e85f60de6f7a1dfc7276e69fecddbc09ad/.typespec/fine-tuning/models.tsp#L328-L329
base model: https://github.com/joseharriaga/openai-in-typespec/blob/610b77e85f60de6f7a1dfc7276e69fecddbc09ad/.typespec/chat/models.tsp#L634

Current thought:
1. This property should be package-private, since all models are in the same package(no models-sub-packages configuration)
2. Access through getter?

### Reproduction

see above

### Checklist

- [x] Follow our [Code of Conduct](https://github.com/microsoft/typespec/blob/main/CODE_OF_CONDUCT.md)
- [x] Check that there isn't already an issue that request the same bug to avoid creating a duplicate.
- [x] Check that this is a concrete bug. For Q&A open a [GitHub Discussion](https://github.com/Microsoft/typespec/discussions).
- [x] The provided reproduction is a [minimal reproducible example](https://stackoverflow.com/help/minimal-reproducible-example) of the bug.