Updates Isaac Sim version in Docker to 2023.1.0-hotfix.1 (#269)

# Description
Updated IsaacSim version in docker .env file to be the latest available
version (2023.1.0-hotfix.1).

## Type of change

- New feature (non-breaking change which adds functionality)

## Checklist

- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./orbit.sh --format`
- [x] 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
- [ ] 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

docker/.env

 # Accept the NVIDIA Omniverse EULA by default
 ACCEPT_EULA=Y
 # NVIDIA Isaac Sim version to use (e.g. 2022.2.1)
-ISAACSIM_VERSION=2022.2.1
+ISAACSIM_VERSION=2023.1.0-hotfix.1
 # Derived from the default path in the NVIDIA provided Isaac Sim container
 DOCKER_ISAACSIM_PATH=/isaac-sim
 # Docker user directory - by default this is the root user's home directory