Codechange: Specify underlying type for all enums excluding those exposed to scripts. (#13383)

src/network/network_gui.h

@@ -38,7 +38,7 @@ struct NetworkCompanyInfo : NetworkCompanyStats {
 	std::string clients;      ///< The clients that control this company (Name1, name2, ..)
 };
 
-enum NetworkRelayWindowCloseData {
+enum NetworkRelayWindowCloseData : uint8_t {
 	NRWCD_UNHANDLED = 0, ///< Relay request is unhandled.
 	NRWCD_HANDLED = 1, ///< Relay request is handled, either by user or by timeout.
 };