[Aether-1761] - Refactor the imagePullSecret for migrating to Fleet

- Avoid to input the credential in helm values.
- Use the sealsecret object in Fleet deployment.

Change-Id: I8036b48caeb23df18622b144cc540386de452705
diff --git a/apps/dbuf/values.yaml b/apps/dbuf/values.yaml
index 1beeaa5..e0289e2 100644
--- a/apps/dbuf/values.yaml
+++ b/apps/dbuf/values.yaml
@@ -5,11 +5,8 @@
   repository: registry.aetherproject.org/tost/dbuf
   pullPolicy: Always
   tag: "latest"
-  credentials: {}
-  # If specified, use this credential to access the image
-  #   registry:
-  #   username:
-  #   password:
+  pullSecrets:
+  #  - name: aether.registry
 
 extraParams:
   - '"-max_queues=1024"'
@@ -24,7 +21,6 @@
   k8s.v1.cni.cncf.io/networks: dbuf-sriov@net0
 
 podSecurityContext: {}
-
 resources:
   requests:
     intel.com/intel_sriov_netdevice: "1"