[JS] Add test for EOS in File Format

Either in a unit test, or in the integration tests

**Reporter**: [Brian Hulette](https://issues.apache.org/jira/browse/ARROW-5688) / @TheNeuralBit
#### Related issues:
- [[JS] Utilize stream EOS in File format](https://github.com/apache/arrow/issues/21891) (relates to)

_{**Note**: *This issue was originally created as [ARROW-5688](https://issues.apache.org/jira/browse/ARROW-5688). Please see the [migration documentation](https://github.com/apache/arrow/issues/14542) for further details.*}