Horde 6 Release steps

One time importing from maintaina -

- Create a FRAMEWORK_6_0 branch from horde master
- Ensure the maintaina-com equivalent is rebased on master already
- PR content from the maintaina-com/FRAMEWORK_6_0 branch into the horde/FRAMEWORK_6_0 branch

Make github actions work

WIP
- CI/PHPUnit, PHPStan
- PHPDOC
- satis

release from console (ignore the release github action for now)

TBD

setup packagist.org integration

TBD