Manually generate tagged images and upload it to download server.
- TESTING_FIRMWARE_*: tag for a testing version
- R_FIRMWARE_*: release branch, from which releases are created and tagged
- T_FIRMWARE_*: tagged release
- FF_UPLOAD_DIR - subdir (e.g. "6.4.4" or "7.0.2-testing") where the firmware should be uploaded
- FF_BUILD_TAG - tag that is displayed in firmare (e.g TESTING_FIRMWARE_6.4.4)
- FF_GITLAB_REMOVE_WORKDIR set it to 1 if workdir should be removed first. else workdir is re-used
- FF_GITLAB_REMOVE_DL set it to 1, if all old downloaded packages should be deleted and downloaded again.