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

@@ -312,6 +312,8 @@
 .build-rauc-bundle:
   extends: .build-image
   variables:
+    # Put timestamp into bundle name.
+    CI_ONIRO_BB_LOCAL_CONF_IMAGE_VERSION_SUFFIX: "-$${DATETIME}"
     CI_ONIRO_JOB_ARTIFACTS: "*.raucb"
   # Avoid pulling in any artifacts from the previous stage.
   dependencies: []