Add note on NM behavior with additional networks

When using additional networks on a dual-stack cluster,
the same network manager connection would be enforced
to all the additional networks. This commit, informes
the users about that behavior and recommends an alternative
if different connections are desired.

Co-authored-by: Max Bridges <mbridges@redhat.com>

Author: MaysaMacedo

modules/install-osp-deploy-dualstack.adoc

@@ -164,4 +164,10 @@ ipv6.addr-gen-mode=0
 ----
 
 After you create and edit the file, reboot the installation host.
+====
+
+[NOTE]
+====
+The `ip=dhcp,dhcp6` kernel argument, which is set on all of the nodes, results in a single Network Manager connection profile that is activated on multiple interfaces simultaneously.
+Because of this behavior, any additional network has the same connection enforced with an identical UUID. If you need an interface-specific configuration, create a new connection profile for that interface so that the default connection is no longer enforced on it.
 ====