UI: When saving on-demand rules, don't set isOnDemandEnabled

When adding or modifying a config, when on-demand options are set by a
user, the rules are saved, but isOnDemandEnabled is left unset (and can
be set by the appropriate control in the detail view (switch in iOS /
button in macOS)).

Signed-off-by: Roopesh Chander <roop@roopc.net>

Sources/WireGuardApp/Tunnel/ActivateOnDemandOption.swift

@@ -42,7 +42,7 @@ extension ActivateOnDemandOption {
             }
         }
         tunnelProviderManager.onDemandRules = rules
-        tunnelProviderManager.isOnDemandEnabled = self != .off
+        tunnelProviderManager.isOnDemandEnabled = false
     }
 
     init(from tunnelProviderManager: NETunnelProviderManager) {