[#1108] ape: Update policy-engine version for listing by iteration

* Update go.mod with a new version of policy-engine pacakge.
* Adapt SwitchRPCGuardedActor to ContractStorage interface.
* Fix `frostfs-adm` util.

Signed-off-by: Airat Arifullin <a.arifullin@yadro.com>

pkg/morph/client/client.go

@@ -579,3 +579,10 @@ func (c *Client) GetActor() *actor.Actor {
 
 	return c.rpcActor
 }
+
+func (c *Client) GetRPCActor() actor.RPCActor {
+	c.switchLock.RLock()
+	defer c.switchLock.RUnlock()
+
+	return c.client
+}