Now digikamdatabase Qt6 based link properly:

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[ 53%] Built target digikamcore_autogen
Consolidate compiler generated dependencies of target digikamcore
[ 53%] Building CXX object core/app/CMakeFiles/digikamcore.dir/utils/digikam_version.cpp.o
[ 53%] Linking CXX shared library libdigikamcore.so
[ 53%] Built target digikamcore
[ 53%] Automatic MOC for target digikamdatabase
[ 53%] Built target digikamdatabase_autogen
[ 53%] Linking CXX shared library libdigikamdatabase.so
[ 53%] Built target digikamdatabase
[ 53%] Automatic MOC for target gui_digikam_obj
[ 53%] Built target gui_digikam_obj_autogen
Consolidate compiler generated dependencies of target gui_digikam_obj
[ 53%] Building CXX object core/app/CMakeFiles/gui_digikam_obj.dir/main/digikamapp_solid.cpp.o
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CCBUGS: 416704