Nbmanips

What's Changed
* ⬆️ Add support for nbconvert 7.0.0 and above by hmiladhia in https://github.com/hmiladhia/nbmanips/pull/21


**Full Changelog**: https://github.com/hmiladhia/nbmanips/compare/v2.1.1...v2.1.2

- Drop support for python 3.8
- Make slightly faster

- Dropped support for Python 3.6 and 3.7
- Added support for Python 3.11 and 3.12
- fix packaging ( dependency specifiers )

🐛 Fix package setup script (add missing sub-packages)

♻️ imrove project structure & performance