File headers: use SPDX license identifiers

check_blender_release/check_module_enabled.py

check_blender_release/check_module_numpy.py

check_blender_release/check_module_requests.py

check_blender_release/check_release.py

check_blender_release/check_static_binaries.py

check_blender_release/check_utils.py

check_blender_release/scripts/modules_enabled.py

check_blender_release/scripts/numpy_basic_operation.py

check_blender_release/scripts/numpy_import.py

check_blender_release/scripts/requests_basic_access.py

check_blender_release/scripts/requests_import.py

check_source/check_descriptions.py

check_source/check_header_duplicate.py

check_source/check_licenses.py

check_source/check_mypy.py

check_source/check_mypy_config.py

check_source/check_spelling.py

check_source/check_spelling_c_config.py

check_source/check_unused_defines.py

git/git_sh1_to_svn_rev.py