[Bug]: Named output tag not present in the expanded output pcollections.

### What happened?

The named output is not preserved after expansion from python expansion service results in a panic.
Code:
```
namedOutput := map[string]typex.FullType{"setOutput": typex.New(outputT)}
result := beam.CrossLanguage(s, "beam:transforms:python:fully_qualified_named", pl, cfg.expansionAddr, beam.UnnamedInput(col), namedOutput)
return result["setOutput"]
```

It throws:
```
panic: missing named output in expanded transform: setOutput is expected in map[None:vAnPEWLGQg_PCollection_PCollection_2] [recovered]
panic: missing named output in expanded transform: setOutput is expected in map[None:vAnPEWLGQg_PCollection_PCollection_2]
```

It should have worked just fine. There are other namedOutput examples [here](https://github.com/apache/beam/blob/4ab557bf98784e51b6f8dca7d89ba5bcea9f04ef/sdks/go/examples/xlang/transforms.go#L97). So it mostly looks like something is not configured correctly from Python side?

### Issue Priority

Priority: 2

### Issue Component

Component: sdk-go