Use GitHub Container Registry images for benchmarks

Use the GitHub Container Registry Docker images for the use case implementation and workload generators.

execution/run_uc.py

@@ -224,7 +224,7 @@ def start_application(svc_yaml, svc_monitor_yaml, jmx_yaml, deploy_yaml,
     app_container = next(filter(
         lambda x: x['name'] == 'uc-application',
         deploy_yaml['spec']['template']['spec']['containers']))
-    app_container['image'] = 'theodolite/theodolite-uc' + uc_id \
+    app_container['image'] = 'ghcr.io/cau-se/theodolite-uc' + uc_id \
         + '-kstreams-app:latest'
 
     # Set configurations environment parameters for SPE