Workalendar

New calendars

- New calendar: Added Tunisia calendar by macharmi (702)
- New calendar: Added El Salvador calendar by hersoncruz (708).

Other changes

- Update China's public holidays for 2023 (728).
- Removed compatibility with Python 3.6, also, removed tests & amended documentation (705).
- Upgraded `tox` usage, now compatble with tox 4+ (added `allowlist_externals`).
- Added support for Python 3.10 (706).
- Added support for Python 3.11 (732).
- Refactor ``NetherlandsWithSchoolHolidays.get_christmas_holidays`` for simplicity and readability.

- Fixed United Kingdom's 2022 holidays ; Added Bank Holiday for the State Funeral of Queen Elizabeth II (719).

New calendars

- New calendar: Added Georgia (country) calendar by atj01 (687).
- New calendar: Added Kazakhstan calendar by atj01 (688).
- New calendar: Added USA Federal Reserve System calendar by ludsoft (695)

Bugfixes and other changes

- Removed duplicate Proclamation Day for Latvia, by Daglina (686).
- Documentation: Fix the ``keep_datetime`` usage example in the "basic" doc (690).
- Added conditional holidays on 26th December and 2nd January in Neuchatel (Switzerland) (697).
- Added Federal Thanksgiving Monday and two conditional holidays on 26th December and 2nd January in Neuchatel (Switzerland) (697).

- Update China's public holidays for 2022, thx to iamsk (693).

- Fixed United Kingdom's 2022 holidays ; Spring Bank Holiday has been moved to the 3rd of June and Queen's Platinum Jubilee added to 2nd of June.
- New calendar: Added Guernsey calendar by ludsoft (681)

New calendar

- New calendar: Added Philippines calendar by micodls (396)

Internal changes

**See the README for more details about requirements, you may have to make changes to your installed packages in your environment.**

- Remove `skyfield` dependency, added `[astronomy]` as extra dependency (660).
- Replace `pyCalverter` with `convertdate` (536).
- Remove unused `JalaliMixin`
- Replace `pkg_resources` with `importlib_metadata` to fetch the version number in `__init__.py` (657)
- Added new badges (pypi, conda, license) and installation instructions (pip, conda) to readme file sugatoray (673).
- Added the "Workalendar maintainers" in the LICENSE file.
- Changed the maintainer email.