OCPBUGS-37864: Update removing a cluster from the ZTP pipeline

Author: amolnar-rh

modules/ztp-site-cleanup.adoc

@@ -17,9 +17,20 @@ You can remove a managed site and the associated installation and configuration
 .Procedure
 
 . Remove a site and the associated CRs by removing the associated `SiteConfig` and `PolicyGenerator` or `PolicyGentemplate` files from the `kustomization.yaml` file.
+
+. Add the following `syncOptions` field to your `SiteConfig` application.
++
+[source,yaml]
+----
+kind: Application
+spec:
+  syncPolicy:
+    syncOptions:
+    - PrunePropagationPolicy=background
+----
 +
 When you run the {ztp} pipeline again, the generated CRs are removed.
 
 . Optional: If you want to permanently remove a site, you should also remove the `SiteConfig` and site-specific `PolicyGenerator` or `PolicyGentemplate` files from the Git repository.
 
-. Optional: If you want to remove a site temporarily, for example when redeploying a site, you can leave the `SiteConfig` and site-specific `PolicyGenerator` or `PolicyGentemplate` CRs in the Git repository.
+. Optional: If you want to remove a site temporarily, for example when redeploying a site, you can leave the `SiteConfig` and site-specific `PolicyGenerator` or `PolicyGentemplate` CRs in the Git repository.