Improve validation when checking for nodeId

Server/utilities/mysqlHandler.js

@@ -110,7 +110,7 @@ exports.getOnlineNodes = (callback) => {
  * @param callback Callback function
  */ 
  async function getNodeInfoFromId(nodeId, callback = undefined) {
-    if (!nodeId) throw new Error("No node ID given when trying to fetch node");
+    if (!nodeId || nodeId == '0' || nodeId == 0 ) throw new Error("No node ID given when trying to fetch node");
     log.DEBUG("Getting node from ID: ", nodeId);
     const sqlQuery = `SELECT * FROM ${nodesTable} WHERE id = ${nodeId}`