Fixes typo in conda environment dependency (#335)

# Description

A typo was in the environment.yml file for conda installation. Fixing
the typo here to avoid installation issues.

## Type of change

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- Bug fix (non-breaking change which fixes an issue)


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## Checklist

- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
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- [x] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
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- [ ] I have updated the changelog and the corresponding version in the
extension's `config/extension.toml` file
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environment.yml

@@ -4,4 +4,4 @@ channels:
 dependencies:
   - python=3.10
   - importlib_metadata
-  - pinocchio===3.4.0  # pip install of pinocchio==3.4.0(required by isaac sim extensions) does not work with numpy<2
+  - pinocchio=3.4.0  # pip install of pinocchio==3.4.0(required by isaac sim extensions) does not work with numpy<2