`FC` environment variable needs to be defined with Python >= 3.12

Currently, build fails with Python 3.12 and Numpy 1.26:

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/conda/staged-recipes/build_artifacts/opentelemac_1700389254610/work/opentelemac/scripts/python3/compile_telemac.py", line 142, in <module>
    main()
  File "/home/conda/staged-recipes/build_artifacts/opentelemac_1700389254610/work/opentelemac/scripts/python3/compile_telemac.py", line 134, in main
    compile_api_files(silent=not options.verbose,
  File "/home/conda/staged-recipes/build_artifacts/opentelemac_1700389254610/work/opentelemac/scripts/python3/compilation/compil_tools.py", line 1038, in compile_api_files
    compile_api_f2py('api', api_dir, source_api, skip_source, ld_flags,
  File "/home/conda/staged-recipes/build_artifacts/opentelemac_1700389254610/work/opentelemac/scripts/python3/compilation/compil_tools.py", line 986, in compile_api_f2py
    raise TelemacException(\
utils.exceptions.TelemacException: Error during the second part of F2PY: 1
Cannot use distutils backend with Python 3.12, using meson backend instead.Traceback (most recent call last):
  File "/home/conda/staged-recipes/build_artifacts/opentelemac_1700389254610/[...]/bin/f2py", line 10, in <module>
    sys.exit(main())
             ^^^^^^
  File "/home/conda/staged-recipes/build_artifacts/opentelemac_1700389254610/[...]/lib/python3.12/site-packages/numpy/f2py/f2py2e.py", line 732, in main
    run_compile()
  File "/home/conda/staged-recipes/build_artifacts/opentelemac_1700389254610/[...]/lib/python3.12/site-packages/numpy/f2py/f2py2e.py", line 610, in run_compile
    from numpy.distutils import fcompiler
ModuleNotFoundError: No module named 'numpy.distutils'

refs:

It will raise an error in Numpy 1.26.3.

Solution:

Define FC when running f2py commands (f2py_name: FC=gfortran f2py ?) for Python >=3.12