AppCallbackImplBase.listTopicSubscriptions is not invoked

## Expected Behavior

AppCallbackImplBase.listTopicSubscriptions should be invoked each time when application is started

## Actual Behavior

AppCallbackImplBase.listTopicSubscriptions is sometimes not invoked when application is starting

## Steps to Reproduce the Problem
- full reproduction path prepared [here](https://github.com/siudeks/repro/tree/siudeks/issue1)

Start with the linked reproduction and trace application startup to the AppCallbackImplBase.listTopicSubscriptions callback. Confirm why the callback is skipped intermittently, then verify that it is invoked each time an application starts.

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