added tendl 2023 generate script

[shimwell]

this PR adds a script that will generate tendl 2023 hdf5 files for openmc

quick setup to build the hdf5 data, tested on ubuntu

pip install openmc_data
python -m pip install --extra-index-url https://shimwell.github.io/wheels openmc
conda install njoy2016 
generate_tendl -r 2023

then look in the tnedl-2023-hdf5 folder