# Description

Previously, while launching the simulation app, there were warnings at
the start of the file that complained that:

```
[Warning] [omni.isaac.kit.simulation_app] Modules: ['omni.isaac.orbit', 'omni.isaac.orbit.app', 'omni.isaac.kit.app_framework'] were loaded before SimulationApp was started and might not be loaded correctly.
[Warning] [omni.isaac.kit.simulation_app] Please check to make sure no extra omniverse or pxr modules are imported before the call to SimulationApp(...)
```

This is because of a manual check inside the `SimulationApp` class where
they check the `sys.modules` against "accepted" packages that are
hardcoded. The PR fixes this issue by removing the orbit packages from
`sys.modules` before launching the simulation app.

## Type of change

- Bug fix (non-breaking change which fixes an issue)

## Checklist

- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./orbit.sh --format`
- [ ] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [x] I have updated the changelog and the corresponding version in the
extension's `config/extension.toml` file