ci: update workflow-template

Remove `--snapshotMode=redo` from kaniko build args

This flag was causing unnecessary rebuilds of layers that
had not changed.  Removing it improves build performance.

Author: in-jun

chart/templates/app/ci/workflow-template.yaml

@@ -110,7 +110,6 @@ spec:
           - "--verbosity=info"
           - "--cache-copy-layers=true"
           - "--cache-run-layers=true"
-          - "--snapshotMode=redo"
           - "--cleanup"
         volumeMounts:
           - name: docker-config