v6.0.0

• BREAKING: Fix issue with httpx support (thanks @parkerhancock) in #784. NOTE: You may have to recreate some of your cassettes produced in previous releases due to the binary format being saved incorrectly in previous releases
• BREAKING: Drop support for boto (vcrpy still supports boto3, but is dropping the deprecated boto support in this release. (thanks @jairhenrique)
• Fix compatibility issue with Python 3.12 (thanks @hartwork)
• Drop simplejson (fixes some compatibility issues) (thanks @jairhenrique)
• Run CI on Python 3.12 and PyPy 3.9-3.10 (thanks @mgorny)
• Various linting and docs improvements (thanks @jairhenrique)
• Tornado fixes (thanks @graingert)