Qt6: QtCharts namespace incompatibility

[thatfuckingbird]

The QtCharts.QtCharts namespace was removed in Qt6, and the contents are now directly in the QtCharts module.
To preserve compatibility with Qt5 code, the below works:

qtpy.QtCharts.QtCharts = qtpy.QtCharts

Maybe this is worth adding in qtpy itself?

[dalthviz]

Hi @thatfuckingbird thank you for the feedback! I'm not totally sure (I guess that gives backwards compatibility with the QtPy 1.x handling that was being done) what do you think @ccordoba12 @CAM-Gerlach ?

[ccordoba12]

Yeah, I think it's a good idea to handle that change here.

[CAM-Gerlach]

Sounds good to me 👍