Updates pip installation docs (#343)

# Description

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Update Isaac Lab pip installation docs to use the included
environment.yml when creating conda env.
This installs all required conda deps for users when using Isaac Sim pip
install method to install Isaac Lab

## Type of change

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- Documentation update

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## 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/pip_installation.rst

@@ -47,7 +47,7 @@ If you encounter any issues, please report them to the
 
          .. code-block:: bash
 
-            conda create -n env_isaaclab python=3.10
+            conda env create -n env_isaaclab -f environment.yml python=3.10
             conda activate env_isaaclab
 
       .. tab-item:: venv environment