Add Qt 6.10 support (requires additional CorePrivate component)

[codeling]

Fixes #94

Hopefully this is the right branch ;)

[dzenanz]

I ran into:

[10/23] Performing configure step for 'PythonQt'
loading initial cache file /home/local/KHQ/dzenan.zukic/Slicer-relQt6/CTK-build/PythonQt-cmake/tmp/PythonQt-cache-RelWithDebInfo.cmake
-- PythonQt: Required Qt components [Core;Widgets;Multimedia;PrintSupport;OpenGL;Network;MultimediaWidgets;UiTools]
-- Could NOT find Cups (missing: CUPS_LIBRARIES CUPS_INCLUDE_DIR) 
-- Configuring done (0.2s)
CMake Error at CMakeLists.txt:348 (target_link_libraries):
  Target "PythonQt" links to:

    Qt6::CorePrivate

  but the target was not found.  Possible reasons include:

    * There is a typo in the target name.
    * A find_package call is missing for an IMPORTED target.
    * An ALIAS target is missing.

and this fixes it for me.

[dzenanz]

@sjh26 I don't have write access to this repository.

[jcfr]

Workflow have been disabled as specific layout of the fork is not yet suitable, mainly because of the use of PyhtonQtConfigure.h specified to this branch (24cebee).

If the topic is forced push one more time, I except no workflows will be triggered.

---

Before integrating this change, I suggest a PR is submitted upstream at https://github.com/MeVisLab/pythonqt and then cherry-picked following the established convention. See history of this branch for reference. In a nutshell commit. message should be prefixed with either [Backport] (if already merged in upstream) or [Backport MR-NNN] if corresponding MR is still being reviewed.

[jcfr]

suggest a PR is submitted upstream

Since upstream does not yet have CMake support, this doesn't apply in this particular case.

[mrbean-bremen]

Since upstream does not yet have CMake support, this doesn't apply in this particular case.

We actually wanted to add cmake support upstream some time ago, but decided to wait for @jcfr (IIRC it was him who volunteered at the time) to back-merge it from this repo.
I think this is the last piece missing to synchronize the repos, after all the awesome work you have done lately👍🏼

[jcfr]

Hi @mrbean-bremen ,

I want very much to make this happen 🚀

Having changed job +2 week or so ago, I am in the process of finalizing how/when I will work on it.

In the meantime, thanks for the patience 🙏