Draft: .oniro-ci: publish rauc bundles for pi4 to hawkbit

This patch-set fixes several issues and inefficiencies related to bundle build process and starts publishing Raspberry Pi 4 builds to HawkBit.

.oniro-ci/build-generic.yaml

@@ -313,8 +313,6 @@
   extends: .build-image
   variables:
     CI_ONIRO_JOB_ARTIFACTS: "*.raucb"
-  script:
-    - !reference [.build-image, script]
 
 # This job is currently used to customize the behavior in oniro and xts-acts.
 # It will be removed when that is safe to do so. It is not documented.