Updates documentation for torch installation for pip installed lab (#553)

# Description

Updates documentation for torch installation to always recommend
installing torch for pip installed Isaac Lab. In the future, Isaac Sim
may not include pytorch into its package, so this would be the
recommended approach regardless of OS.


## Type of change

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applicable. -->

- 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/setup/installation/isaaclab_pip_installation.rst

@@ -51,7 +51,7 @@ To learn about how to set up your own project on top of Isaac Lab, see :ref:`tem
                   env_isaaclab\Scripts\activate
 
 
--  Next, install a CUDA-enabled PyTorch 2.7.0 build for CUDA 12.8. This step is optional for Linux, but required for Windows to ensure a CUDA-compatible version of PyTorch is installed.
+-  Next, install a CUDA-enabled PyTorch 2.7.0 build for CUDA 12.8.
 
    .. code-block:: bash