Lyra: GA_Melee uses disallowed NetMulticast RPC for melee impact sound

The melee gameplay ability GA_Melee uses a NetMulticast RPC which isn't allowed and causes a blueprint validation error:

GA_Melee.uasset: Gameplay Abilities are not replicated to Simulated Proxies and therefore NetMulticast Function MeleeImpact is meaningless

NetMulticast RPCs on GAs used to work, because abilities UObjects were replicated to all clients but this was unintentional behavior. Nowadays they don't replicate to sim proxies anymore, so the NetMulticast won't work. With the current implementation players can hear their own melee attacks, but not those of other players and bots (unless they are listen server). The hit FX (melee impact sound) should be played in a different way, like GameplayCueNotifies.

• Open Lyra Starter Game
• Open the GA_Melee gameplay ability blueprint
• Observe it contains a NetMulticast RPC, which won't execute on clients on which the gameplay ability doesn't exist. It will only execute on servers and the autonomous proxy.