UI: Don't show WHIP in stream settings if the protocol isn't registered

UI/window-basic-settings-stream.cpp

@@ -387,7 +387,10 @@ void OBSBasicSettings::LoadServices(bool showAll)
 	for (QString &name : names)
 		ui->service->addItem(name);
 
-	ui->service->insertItem(0, QTStr("WHIP"), QVariant((int)ListOpt::WHIP));
+	if (obs_is_output_protocol_registered("WHIP")) {
+		ui->service->insertItem(0, QTStr("WHIP"),
+					QVariant((int)ListOpt::WHIP));
+	}
 
 	if (!showAll) {
 		ui->service->addItem(