Fixes broken link in doc (#3274)

# Description

Fixes a broken link in the docs to point to the feature/newton branch.

## Type of change

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- Bug fix (non-breaking change which fixes an issue)
- This change requires a documentation update

## Checklist

- [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
- [ ] 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
- [ ] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there

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docs/source/experimental-features/newton-physics-integration/index.rst

@@ -8,7 +8,7 @@ simulation, modern Python APIs, and a flexible architecture for both users and d
 Newton is an Open Source community-driven project with contributions from NVIDIA, Google Deep Mind, and Disney Research,
 managed through the Linux Foundation.
 
-This `experimental feature branch <https://isaac-sim.github.io/IsaacLab/main/source/experimental-features/index.html>`_ of Isaac Lab provides an initial integration with the Newton Physics Engine, and is
+This `experimental feature branch <https://github.com/isaac-sim/IsaacLab/tree/feature/newton>`_ of Isaac Lab provides an initial integration with the Newton Physics Engine, and is
 under active development. Many features are not yet supported, and only a limited set of classic RL and flat terrain locomotion
 reinforcement learning examples are included at the moment.