Log Message:
py-sphobjinv: updated to 2.3.1.2

2.3.1.2

Internal

* **DOC RENDERING FIX**: The `super` keyword used in a statement in the HTML footer
  template was missing parentheses to perform a method call; this
  caused the template rendering to emit a Python string describing
  the parent template object, instead of rendering the parent
  template as intended.
* Moved the Sphinx linkcheck job out of CI and into `tox`.
  * The linkcheck is often flaky, and is a nuisance when it fails the CI. For
    uncertain reasons, the flakiness has increased noticeably in recent
    months. Less-frequent link checking, at release-time, is sufficient; so,
* Renamed `.readthedocs.yml` to `.readthedocs.yaml` to comply with the new,
  strict RtD requirement.
* Added read-only GitHub PAT to Azure Pipelines config to ensure Python 3.13
  retrieval from GitHub doesn't hit a rate limit.
* Update flake8 version pin in `requirements-flake8.txt` to avoid a bug in
  `pycodestyle`.
* Removed `.pre-commit-config.yaml`, to remove the expectation of using
  pre-commit from the project.
* For a project with this low an external contribution volume, the costs
   outweigh the benefits.
* Added a `black` environment to `tox` for convenience and better
  encapsulation.
* Added `flake8-black` to `requirements-flake8.txt` so that blackened status
  is checked as part of the linting, whether run manually or in CI.

Administrative

* Added support for Python 3.13.
* Dropped support for Python 3.8 (EOL).
* Revised and updated `CONTRIBUTING.md`.
* Updated link target of Pepy badge to match the new URL format.
* Bumped Read the Docs Python version to 3.12.