How to use await in JUnit cleanup?

In my cleanup function I would like to clear Firebase Realtime Database (emulator).. but to be sure it has succeeded before it goes to the next test, I have to call await..

@After
fun cleanup() {
   ...
   instance.reference.setValue(null).await()
}

However, the cleanup function can not be suspend function.. so how could I achieve this?

thanks!

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