Registry pruning added to ROSA documentation.

Author: eohartman

registry/index.adoc

@@ -16,6 +16,7 @@ include::modules/registry-integrated-openshift-registry.adoc[leveloffset=+1]
 
 * xref:../registry/configuring-registry-operator.adoc#configuring-registry-operator[Image Registry Operator in {product-title}]
 
+include::modules/pruning-images.adoc[leveloffset=+1]
 include::modules/registry-third-party-registries.adoc[leveloffset=+1]
 
 include::modules/registry-quay-overview.adoc[leveloffset=+1]