SPDX identifier is missing
Many open source licenses are uniquely identified with an SPDX identifier
See for example the Apache 2.0 license: https://spdx.org/licenses/Apache-2.0.html
SPDX is missing from the list of identifiers: https://gitlab.hzdr.de/hmc/hmc/cct-1-mapping/category-definitions/-/blob/master/hmc_schemas/hmc_license_1_0_0.json