I need to change the text of button that's in the sysTray area, this is my JS code

odoo.define('custom.systray', function (require) {
"use strict";

    var SystrayMenu = require('web.SystrayMenu');
    var Widget = require('web.Widget');
    var Rpc = require('web.rpc');
    var Core = require('web.core');
    var Session = require('web.session')
    var ListView = require('web.ListView');
    var ListController = require("web.ListController");
    var Model = require("web.Model");
    var view_dialogs = require('web.view_dialogs');
    var titulo_etiqueta = "Choose Entity"

    function inicializar() {
        var self = this;

        var systemTrayMenuEntidades = Widget.extend({
            label: titulo_etiqueta,
            template: 'systray.menu.entidad',
            events: {
                    "click": 'on_click',
            },
            on_click: function (event) {
                new view_dialogs.SelectCreateDialog(this, {
                    res_model: 'entidades',
                    title: 'Choose entity',
                    no_create: true,
                    disable_multiple_selection: true,
                    on_selected: function (records) {
                        var record_ids = records.map(function(item){
                             return item['id'];
                        });
                        console.log(record_ids[0])
                        var etiqueta = Rpc.query({
                            model: "entidades",
                            method: 'search_read',
                            domain: [['id','=',record_ids[0]]],
                        })
                        .then(function (id_entidad) {
                            console.log('************ Get data %s ************', id_entidad[0].name)
                            titulo_etiqueta = id_entidad[0].name

                        });
                        console.log(records)
                    }
                }).open();
            }
        });

        SystrayMenu.Items.push(systemTrayMenuEntidades);
    }
    inicializar();

});