[FTBFS] qt3d and qtmultimedia have a conflicting CMake target name

CMake Error at qtbase/cmake/QtExecutableHelpers.cmake:28 (add_executable):
  add_executable cannot create target "tst_qcamera" because another target
  with the same name already exists.  The existing target is an executable
  created in source directory
  "/home/tjmaciei/src/qt/qt6-release/qt3d/tests/auto/render/qcamera".  See
  documentation for policy CMP0002 for more details.
Call Stack (most recent call first):
  qtbase/cmake/QtTestHelpers.cmake:214 (qt_internal_add_executable)
  qtmultimedia/tests/auto/unit/multimedia/qcamera/CMakeLists.txt:7 (qt_internal_add_test)


CMake Error at qtbase/cmake/QtTestHelpers.cmake:337 (add_custom_target):
  add_custom_target cannot create target "tst_qcamera_check" because another
  target with the same name already exists.  The existing target is a custom
  target created in source directory
  "/home/tjmaciei/src/qt/qt6-release/qt3d/tests/auto/render/qcamera".  See
  documentation for policy CMP0002 for more details.
Call Stack (most recent call first):
  qtmultimedia/tests/auto/unit/multimedia/qcamera/CMakeLists.txt:7 (qt_internal_add_test)