Remove: Debug redirect over network

It does not work for dedicated servers because upon starting the process to
resolve the address to redirect to gets killed. Also with all the async going
on in the network code, the debug redirection will start very late in the
process.

src/network/network_func.h

@@ -47,7 +47,6 @@ void NetworkDisconnect(bool close_admins = true);
 void NetworkGameLoop();
 void NetworkBackgroundLoop();
 std::string_view ParseFullConnectionString(const std::string &connection_string, uint16_t &port, CompanyID *company_id = nullptr);
-void NetworkStartDebugLog(const std::string &connection_string);
 void NetworkPopulateCompanyStats(NetworkCompanyStats *stats);
 
 void NetworkUpdateClientInfo(ClientID client_id);