Bug 500504

SUMMARY

```
runtime: org.kde.Platform
runtime-version: "6.8"
sdk: org.kde.Sdk
```

In cmake, find_package(Qt blabla.. SCXML)  started failing a week or so ago when trying to build an aarch64 flatpak. Works fine with the x64 toolchain & version for the exact same source.

Example of a build that fails: https://github.com/ossia/score/actions/runs/13403974706/job/37440378074

```
-- Could NOT find Qt6StateMachine (missing: Qt6StateMachine_DIR)
CMake Error at CMakeLists.txt:204 (find_package):
  Found package configuration file:

    /usr/lib/aarch64-linux-gnu/cmake/Qt6/Qt6Config.cmake

  but it set Qt6_FOUND to FALSE so package "Qt6" is considered to be NOT
  FOUND.  Reason given by package:

  Failed to find required Qt component "StateMachine".

  Expected Config file at
  "/usr/lib/aarch64-linux-gnu/cmake/Qt6StateMachine/Qt6StateMachineConfig.cmake"
  exists



  Configuring with --debug-find-pkg=Qt6StateMachine might reveal details why
  the package was not found.

  Configuring with -DQT_DEBUG_FIND_PACKAGE=ON will print the values of some
  of the path variables that find_package uses to try and find the package.

```
SOFTWARE/OS VERSIONS
As provided by flathub on a Github Actions runner