NeyworkDiscovery component has "useNetworkManager" flag set to true - this cause warning when user don't use NetworkManager in this scene

The correct behavior would be:
- to check if there is NetworkManager component in the scene and only then set this flag to true
OR
- simply set this flag to false by default

How we can reproduce it using the example you attached
1 Open attached project
2 Open scene "sc1" and press Play
3 Notice warning in console:
"NetworkDiscovery broadcast data changed while using NetworkManager. This can prevent clients from finding the server. The format of the broadcast data must be 'NetworkManager:IPAddress:Port'."

Actual result: that warning is expected and caused by "useNetworkManager" flag set to true (but in the script we are trying to change "broadcast data")
Expected result: "useNetworkManager" flag SHOULD NOT be set to true by default