# Description

This MR does the following:

* Adds parsing of instanced prims in
`isaaclab.sim.utils.get_all_matching_child_prims` and
`isaaclab.sim.utils.get_first_matching_child_prim`. Earlier, instanced
prims were skipped since `Usd.Prim.GetChildren` does not return
instanced prims.
* Adds parsing of instanced prims in
`isaaclab.sim.utils.make_uninstanceable` to make all prims
uninstanceable.

These are needed to parse meshes for the dynamic raycaster class in
#3298

## Type of change

- Bug fix (non-breaking change which fixes an issue)
- New feature (non-breaking change which adds functionality)
- Breaking change (fix or feature that would cause existing
functionality to not work as expected)

## Checklist

- [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
- [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

---------
Signed-off-by: Mayank Mittal <12863862+Mayankm96@users.noreply.github.com>
Co-authored-by: Kelly Guo <kellyg@nvidia.com>