gh-39944: Include optional packages in `pyproject.toml` and conda environments
    
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Adds the missing information about optional dependencies in the
`pyproject.toml` and use this updated info to include these packages
also in the conda environment.


### 📝 Checklist

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### ⌛ Dependencies

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- (Upstream conda/grayskull#612)
- conda-forge/cypari2-feedstock#57
    
URL: #39944
Reported by: Tobias Diez
Reviewer(s): Isuru Fernando

Author: Release Manager