Don't set username on NETunnelProviderProtocol

The username corresponds to the Account field in iOS system VPN UI,
but if we don't set it, the field is not shown, so setting it isn't
really required.

WireGuard/Shared/Model/NETunnelProviderProtocol+Extension.swift

@@ -32,9 +32,6 @@ extension NETunnelProviderProtocol {
         } else {
             serverAddress = "Multiple endpoints"
         }
-
-        //TODO(roopc): Why are we doing this? Just for kicks? Is it useful? Seems needless.
-        username = tunnelConfiguration.name
     }
 
     func asTunnelConfiguration(called name: String? = nil) -> TunnelConfiguration? {