Integrate gitlab-ci/generate_firmware_json

Commit: seco-ne/yocto/infrastructure/gitlab-ci@51e0cf67

build:stages: Add Firmware Package JSON stage

The old Alphaplan stage is deprecated and was removed in a prior commit. Add new stage to generate the Firmware Package JSON files that do replace the old Alphaplan articles.

Source merge request: seco-ne/yocto/infrastructure/gitlab-ci!371 (merged)

mentioned in merge request seco-ne/yocto/infrastructure/gitlab-ci!371 (merged)

merged