v3.9.0

• VM: set the matplotlib backend to tkagg
• Updated Versions:
  • CIL: numpy-2 branch (v25+)
  • STIR: 6.3.0
  • SIRF: 3.9.0
  • ITK: 5.4.4
  • parallelproj: 1.10.2
  • boost: 1.85.0 (maximum supported by Gadgetron)
  • CCPi-Regularisation-Toolkit: v25.0.0
  • SWIG: 4.4
• Docker:
  • separate build & test steps
  • fix missing site-packages
  • STIR_DISABLE_HDF5=ON pending future fix (see #980)
• CMake:
  • Use new FindPython module. You might need to help it find the correct Python path, e.g. by setting Python_ROOT_DIR.
  • Use IPP_ROOT instead of IPP_LIBRARY (for BUILD_CIL)
  • Suppress compilation warnings for Gadgetron for future compatibility (as Gadgetron converts them to errors)
  • Support the Gadgetron_EXTRA_CMAKE_ARGS option
  • Add SIRF_DISABLE_Gadgetron_toolboxes convenience flag
  • fix HDF5 problems related to finding C/CXX components & version restrictions
  • update & cleanup CIL tests, add unittest-parametrize
  • fix ISMRMRD build (c++17, cURL docker patch)