qdoc non-deterministic .index output

While working on reproducible builds for openSUSE, I found that various packages have variations in their doc build. E.g. our qt6-datavis3d-docs-html varies in /usr/share/doc/qt6/qtdatavis3d/qtdatavis3d.index because a section
{{<page name="qmlaxishandling" }}
moved.
 
Other affected packages include:
qt6-3d qt6-base qt6-charts qt6-connectivity qt6-graphs qt6-grpc qt6-multimedia qt6-positioning qt6-remoteobjects qt6-scxml qt6-serialbus qt6-tools qt6-websockets
 
I did not observe this issue with previous Qt-6.8.2