Add consolidated demo script for showcasing recording and mimic dataset generation in real-time in one simulation script (#189)

This PR adds `consolidated_demo.py` script that runs teleop-recording
and real-time mimic dataset generation in the same simulation with
multi-env to showcase the mimic workflow in one script.

It includes changes and fixes needed to enable recording and running
mimic at the same time under multi-env setting.

<!-- As a practice, it is recommended to open an issue to have
discussions on the proposed pull request.
This makes it easier for the community to keep track of what is being
developed or added, and if a given feature
is demanded by more than one party. -->

<!-- As you go through the list, delete the ones that are not
applicable. -->

- Bug fix (non-breaking change which fixes an issue)
- New feature (non-breaking change which adds functionality)

- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./isaaclab.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
- [x] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there

<!--
As you go through the checklist above, you can mark something as done by
putting an x character in it

For example,
- [x] I have done this task
- [ ] I have not done this task
-->

---------
Co-authored-by: Kelly Guo <kellyg@nvidia.com>