Includes updates to core through commit: [3ce0b18](https://github.com/PreTeXtBook/pretext/commit/3ce0b18284473f5adf52cea46374688299b6d643)
Added
- `pretext update` command will update managed files and the `requirements.txt` file to match current installed version of PreTeXt.
Changed
- Improved help when deploy fails.
- Managed files (`project.ptx`, `requirements.txt`, etc) are now managed by comparing to stock versions, not by a magic comment at top.
- Only manage git-related files (`.gitignore`, `.devcontainer.json`, `.github/workflows/pretext-cli.yml`) when project is tracked by git.
- Only updates managed files when `pretext update` is run, instead on every run.
- Only check for new pretext version once a day.
Fixed
- Removed unneeded warnings about pretext projects existing or not when running `pretext upgrade` and `pretext new`.