Add ICSP note to OLM mirror proc

Author: adellape

modules/olm-mirroring-catalog.adoc

@@ -187,15 +187,19 @@ If you used the `--manifests-only` flag during the mirroring process and want to
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 --
 
-. On a host with access to the disconnected cluster, create the `ImageContentSourcePolicy` object by running the following command to specify the `imageContentSourcePolicy.yaml` file in your manifests directory:
+. On a host with access to the disconnected cluster, create the `ImageContentSourcePolicy` (ICSP) object by running the following command to specify the `imageContentSourcePolicy.yaml` file in your manifests directory:
 +
 [source,terminal,subs="attributes+"]
 ----
 $ oc create -f <path/to/manifests/dir>/imageContentSourcePolicy.yaml
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 +
 where `<path/to/manifests/dir>` is the path to the manifests directory for your mirrored content.
-
++
+[NOTE]
+====
+Applying the ICSP causes all worker nodes in the cluster to restart. You must wait for this reboot process to finish cycling through each of your worker nodes before proceeding.
+====
 
 You can now create a `CatalogSource` object to reference your mirrored index image and Operator content.