OSDOCS-13238 RODOO admonition added

Author: cbippley

modules/rodoo-about.adoc

@@ -13,3 +13,8 @@ Cluster administrators can use the {run-once-operator} to force a limit on the t
 To apply the run-once duration override from the {run-once-operator} to run-once pods, you must enable it on each applicable namespace.
 
 If both the run-once pod and the {run-once-operator} have their `activeDeadlineSeconds` value set, the lower of the two values is used.
+
+[NOTE]
+====
+You cannot install the {run-once-operator} on clusters managed by the HyperShift Operator.
+====