fix: update IMAGE_DIGEST reference in kustomization

Author: rust84

kubernetes/apps/selfhosted/cookjam/ks.yaml

@@ -15,7 +15,7 @@ spec:
   path: ./kubernetes/apps/selfhosted/cookjam/app
   postBuild:
     substitute:
-      IMAGE_DIGEST: sha256:092363186eb3045cda9954d92e8b3c736f6797d1b00263ca673ffbe0ee53006b # {"$imagepolicy": "flux-system:cookjam-policy:digest"}
+      IMAGE_DIGEST: sha256:092363186eb3045cda9954d92e8b3c736f6797d1b00263ca673ffbe0ee53006b # {"$imagepolicy": "selfhosted:cookjam-dev:digest"}
   prune: true
   sourceRef:
     kind: GitRepository