community/py3-pyqt6-webengine: upgrade to 6.6.0

Recent changes from changelog:

2023-10-25 Phil Thompson phil@riverbankcomputing.com

* NEWS, rb-product.toml:
Removed an out of date entry in the product file.
[6b4eda057dbf] [6.6.0]

2023-10-22 Phil Thompson phil@riverbankcomputing.com

* NEWS, PyQt6-WebEngine.msp:
Updated for Qt v6.6.
[618f2f9800e9]