Acts 36 is not happy with envelope26

[veprbl]

Steps to reproduce: (give a step by step account of how to trigger the bug)

1. run 25.07.0-stable container
2. try to produce a material map for any epic version (e.g. 25.08.0) that includes fix: put BIC 1st layer in separate envelope for Acts conversion #912

Expected Result: (what do you expect when you execute the steps above)

Geometry gets loaded.

Actual Result: (what do you get when you execute the steps above)

++ python material_recording_epic.py -i prefix/share/epic/epic_craterlake_material_map.xml -n 1000 -t 5000 -o geant4_material_tracks.root
Error in <TGeoVoxelFinder::SortAll>: Wrong bounding box for volume envelope26
Traceback (most recent call last):
  File "/tmp/mm2/epic_25_07_0/scripts/material_map/material_recording_epic.py", line 77, in <module>
    main()
  File "/tmp/mm2/epic_25_07_0/scripts/material_map/material_recording_epic.py", line 60, in main
    detector, trackingGeometry, decorators = epic.getDetector(
                                             ^^^^^^^^^^^^^^^^^
  File "/tmp/mm2/epic_25_07_0/scripts/material_map/epic.py", line 47, in getDetector
    trackingGeometry, deco = detector.finalize(dd4hepConfig, matDeco)
                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
RuntimeError: Detector Element has no VariantParameters