Type info Added to gradient.py and inv_spinctrl.py (invesalius#787)

* Formmatted and fixed linting error with ruff.

Also marked get_physical_memory and predict_memory as deprecated since they were not used anywhere.

* Added Exception after except to avoid handling base Exceptions such as ctrl-C

* type hinted utils.py

* added Tuple, and List for py38 compatibility

formatted and removed python2's import ordereddict statement in slice_menu.py

* Added type info to slice_menu.py

* fixed ruff linting errors

* Removed unused import

removed old super() arguments

* commented unused variables

* removed old wx version line

* Annotated ranges as ints

* Type hinted function parameters and return types of inv_spinctrl.py

* type hinted function signatures in gradient.py

* removed ChangeMinValue and ChangeMaxValue deprecated functions

* Added annotations for colourtype

Changed GradientDisp and GradientNoSlide api

* Annotated unknown Events as Any

* Added SpinEvent and FocusEvent types