private String mapToQueryString(Map<String, Object> params) {
		return params.entrySet().stream()
			.map(param -> param.getKey() + "=" + param.getValue())
			.reduce((param1, param2) -> param1 + "&" + param2)
			.orElse("");
	}
Convert {@link Map} to query string.
ngrinder-controller/src/main/java/org/ngrinder/infra/webhook/service/NGrinderWebhookClient.java