Qt6 port : All Unit-tests compile now.

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[100%] Automatic MOC for target IOJobsTest
[100%] Built target facesenginedemo_gui_autogen
[100%] Built target convert_format_cli_autogen
[100%] Built target renamecustomizer_utest
[100%] Built target IOJobsTest_autogen
[100%] Built target cameranamehelper_utest
[100%] Built target albummodel_utest
[100%] Built target advancedrename_utest
[100%] Built target checkdatabaseswitch_cli
[100%] Built target checkdatabaseinit_cli
[100%] Built target databasefields_utest
[100%] Built target databasetags_utest
[100%] Built target align_gui
[100%] Built target preprocess_gui
Consolidate compiler generated dependencies of target face_rec_cli
[100%] Built target detect_gui
[100%] Built target benchmark_dnndetection_gui
[100%] Built target recognize_cli
[100%] Building CXX object core/tests/facesengine/recognition/CMakeFiles/face_rec_cli.dir/face_rec_cli.cpp.o
[100%] Built target benchmark_recognition_cli
[100%] Built target recognition_gui
[100%] Built target traindb_cli
[100%] Built target facesenginedemo_gui
[100%] Built target IOJobsTest
[100%] Built target convert_format_cli
[100%] Linking CXX executable face_rec_cli
[100%] Built target face_rec_cli
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TODO : check if libksane based code and Marble based code compile with Qt6. Both still unavailable for the moment.
CCBUGS: 416704