In single-app mode, the component with the specified slug gets launched
automatically, essentially behaving as a normal app.

Defaults to multi-app mode.

For more details, see [its dedicated page](Single-app-Mode).

<details>
<summary>History</summary>

- [[1.3.0](https://github.com/microsoft/react-native-test-app/releases/tag/1.3.0)]
  Added

</details>
