Add notes on SHACL2CODE_SPDX_DIR env var#32

bact wants to merge 3 commits into

spdx:mainspdx/spdx-python-model:mainfrom

bact:doc-shacl2code-spdx-dirbact/spdx-python-model:doc-shacl2code-spdx-dirCopy head branch name to clipboard