deskutils/hebcal: update to 4.13
- Switch to USE_GITHUB
- Improve the COMMENT line description
- Add regression-test target
- Improve the content of pkg-descr
- Update WWW in pkg-descr
- Pass maintainership to submitter
Changelog: https://github.com/hebcal/hebcal/releases/tag/v4.13
PR: 221142
Submitted by: Ryder Dain <rtd24@columbia.edu>