[Unit tests] test_acousticraytracer_tools fails sometimes

User story :
As Tympan team, I want test_acousticraytracer_tools always succeeds, in order not to occasionally break CI.

How to reproduce :
Adapt '2_Release_Tests_Unitaires.bat' this way :
ctest -C Release -R test_acousticraytracer_tools --repeat until-fail:100 --output-on-failure