Changes proposed in this Pull Request

Fix two typos in the documentation; one in LineType attributes, another in the docstring of the get_bounds_pu() function.

Checklist

• Code changes are sufficiently documented; i.e. new functions contain docstrings and further explanations may be given in docs.
• Unit tests for new features were added (if applicable).
• A note for the release notes docs/release-notes.md of the upcoming release is included.
• I consent to the release of this PR's code under the MIT license.