Seems that the '5' enforces the major version and it refuses to find
system's assimp-6.0.2 (which is perfectly usable given Qt 6.9.2 bundles
that version without it).

We don't package older ones, so drop the check as a quick workaround.

https://bugreports.qt.io/browse/QTBUG-137996
--- a/src/core/configure.cmake
+++ b/src/core/configure.cmake
@@ -16 +16 @@
-qt_find_package(WrapQt3DAssimp 5 PROVIDED_TARGETS WrapQt3DAssimp::WrapQt3DAssimp MODULE_NAME 3dcore QMAKE_LIB qt3d-assimp)
+qt_find_package(WrapQt3DAssimp PROVIDED_TARGETS WrapQt3DAssimp::WrapQt3DAssimp MODULE_NAME 3dcore QMAKE_LIB qt3d-assimp)
@@ -23 +23 @@
-                   PACKAGES PACKAGE WrapQt3DAssimp 5
+                   PACKAGES PACKAGE WrapQt3DAssimp