Fix test suite error with optional dependency not installed

[ericpre]

Fix test suite error when pyebsdindex is not installed, add build to test without optional dependencies.

Progress of the PR

• [n/a] Docstrings for all functions
• [n/a] Unit tests with pytest for all lines
• [x] Clean code style by running black via pre-commit

For reviewers

• [ ] The PR title is short, concise, and will make sense 1 year later.
• [ ] New functions are imported in corresponding __init__.py.
• [ ] New features, API changes, and deprecations are mentioned in the unreleased section in CHANGELOG.rst.
• [ ] New contributors are added to release.py, .zenodo.json and .all-contributorsrc with the table regenerated.