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

# Description

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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.

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## 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

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Author: xyao-nv

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