Adds link to IsaacLabEvalTasks repo from mimic section in doc (#3621)

# Description

<!--
Thank you for your interest in sending a pull request. Please make sure
to check the contribution guidelines.

Link:
https://isaac-sim.github.io/IsaacLab/main/source/refs/contributing.html

💡 Please try to keep PRs small and focused. Large PRs are harder to
review and merge.
-->

Isaac Lab Mimic section is disjoint from [IsaacLabEvalTask
repo](https://github.com/isaac-sim/IsaacLabEvalTasks/tree/main) which
uses Mimic to generate Nut pouring task and Pipe sorting task for GR00T
post-training and closedloop evaluation. Added a pointer in the doc.

<!-- 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. -->

## Type of change

Documentation update

## Checklist

- [x] I have read and understood the [contribution
guidelines](https://isaac-sim.github.io/IsaacLab/main/source/refs/contributing.html)
- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./isaaclab.sh --format`
- [x] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [x] 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
-->

CONTRIBUTORS.md

@@ -135,6 +135,7 @@ Guidelines for modifications:
 * Vladimir Fokow
 * Wei Yang
 * Xavier Nal
+* Xinjie Yao
 * Xinpeng Liu
 * Yang Jin
 * Yanzi Zhu

docs/source/overview/imitation-learning/teleop_imitation.rst

@@ -604,6 +604,10 @@ Record the normalization parameters for later use in the visualization step.
 .. note::
    By default the trained models and logs will be saved to ``IsaacLab/logs/robomimic``.
 
+You can also post-train a `GR00T <https://github.com/NVIDIA/Isaac-GR00T>`__ foundation model to deploy a Vision-Language-Action policy for the task.
+
+Please refer to the `IsaacLabEvalTasks <https://github.com/isaac-sim/IsaacLabEvalTasks/>`__ repository for more details.
+
 .. _visualize-results-demo-2:
 
 Visualize the results