Release v2.3.1

Changed

• actions/setup-python from v4.6.1 to v4.7.1.
• actions/checkout from v3.5.2 to v4.1.1.
• peter-evans/create-pull-request from v5.0.1 to v5.0.2.
• pypa/gh-action-pypi-publish from from v1.4.2 to v1.8.10.
• pre-commit-hooks from v4.4.0 to v4.5.0.
• sphinx from ^7.0.1 to ^7.1.2.
• invoke from ^2.1.2 to ^2.2.0.
• pre-commit from ^3.3.2 to ^3.5.0.
• black from ^23.3.0 to ^23.11.0.
• mypy from ^1.3.0 to ^1.7.0.
• safety from ^2.4.0b1 to ^2.4.0b2.
• pytest from ^7.3.1 to ^7.4.3.
• xdoctest from ^1.1.1 to ^1.1.2.
• coverage from ^7.2.6 to ^7.3.2.
• click from ^8.1.3 to ^8.1.7.
• flake8-builtins from ^2.1.0 to ^2.2.0.

Fixed

• readthedocs config.