#tf-data Fix the graph mode tests for index flat map.
#tf-data Fix the graph mode tests for index flat map.

Otherwise, I'm getting this error:
```
Tensor("Const:0", shape=(4, 3), dtype=int64) must be from the same graph
 as Tensor("TensorSliceDataset:0", shape=(), dtype=variant)
```

FUTURE_COPYBARA_INTEGRATE_REVIEW=https://github.com/openxla/xla/pull/11353 from jaro-sevcik:host-offloading-async-fusion-dynamic-slicing 905db6df8130300014728bf4eceb2ee2fc23d6e1
