Updates and bug fixes

@jeylau

What's Changed

Pull demo data from Zenodo by @jeylau in #2440
Update maDLC_UserGuide.md by @Timokleia in #2446
Fix bug dataset and metadataset fixes #2390 by @Tetra-quark in #2405
Bug fix: add_new_videos(..., extract_frames=True) by @n-poulsen in #2468
bug fix: empty predictions during video analysis by @n-poulsen in #2467
Update README.md by @MMathisLab in #2464
Update AUTHORS by @MMathisLab in #2475
updated macOS runner to 13 by @n-poulsen in #2484
Update README.md by @Timokleia in #2496
Bump version of tables installed during CI by @jeylau in #2500
updated COLAB notebooks to install a CUDA version compatible with DLC by @n-poulsen in #2506
updated package requirements by @n-poulsen in #2513
Test for the presence of snapshot files when using modelzoo by @jeylau in #2485
Version update by @AlexEMG in #2514

Full Changelog: v2.3.8...v2.3.9