code: async function routeDelete(target, rootPwd) {
      const prevRoutes = await searchPrevRoutes(target);
      if (prevRoutes.length == 0) {
          return; // no need to do anything
      }
      const cmds = [];
      for (const prevRoute of prevRoutes) {
          cmds.push([
              'nmcli', 'connection', 'modify', prevRoute.connName,
              '-ipv4.routes', `${prevRoute.target} ${prevRoute.gatewayIP}`]);
          cmds.push(['nmcli', 'connection', 'down', prevRoute.connName]);
          cmds.push(['nmcli', 'connection', 'up', prevRoute.connName]);
      }
      return await executeCommands(cmds, null, {sudo: true, password: rootPwd});
  }
docs: Delete static route from ipv4 network
  @param {string} target : the destination network or host. e.g. 224.0.23.0/32
  @param {string} rootPwd : root password for executing sudo
  @return {Promise} Return standard output of each command as an array