Selenium runs tests then automatically closes the browser

//import seleniun package
const selenium = require("selenium-webdriver");

//require browser driver for google Chrome
require("chromedriver");

//use Selenium By Library
const By = selenium.By;

const HomePage = require("./pages/home");

//build pattern to access webpage.
const driver = new selenium.Builder()
   .forBrowser("chrome")
   .build();

const homePage = new HomePage(driver);
homePage.open();

//array of invitees
const invitees = [
    'Gonzalo Torres del Fierro',
    'Shadd Anderson',
    'George Aparece',
    'Shadab Khan',
    'Joseph Michael Casey',
    'Jennifer Nordell',
    'Faisal Albinali',
    'Taron Foxworth',
    'David Riesz',
    'Maicej Torbus',
    'Martin Luckett',
    'Joel Bardsley',
    'Reuben Varzea',
    'Ken Alger',
    'Amrit Pandey',
    'Rafal Rudzinski',
    'Brian Lynch',
    'Lupe Camacho',
    'Luke Fiji',
    'Sean Christensen',
    'Philip Graf',
    'Mike Norman',
    'Michael Hulet',
    'Brent Suggs'
 ];

//perform actions
//addInvitee("first name");
//addInvitee("last name");

//invitees.forEach(invitee => homePage.addInvitee(invitee));
invitees.forEach(homePage.addInvitee, homePage); 

//call the functions

homePage.removeInvitee("Shadd Anderson");

homePage.toggleNonRespondersVisibility();

const By = require("selenium-webdriver").By;

class HomePage {

    constructor(driver) {
        //store reference to the driver in instance
        this.driver = driver;
        //JavaScript Object Literal
        this.locators = {
            inviteeForm: By.id("registrar"),
            inviteeNameField: By.name("name"),
            toggleNonRespondersVisibility: By.css(".main > div input"),
            removeButtonForInvitee: invitee => By.xpath(`//span[text() = "${invitee}"]/../button[last()]`)

        };

    }

    open() {
        //open URL
        this.driver.get(process.env.URL);
    } 

    //keep it DRY with functions
    addInvitee(name) {
        this.driver.findElement(this.locators.inviteeNameField)
            .sendKeys(name);
        this.driver.findElement(this.locators.inviteeForm).submit();

    }

    removeInvitee(invitee) {
        this.driver.findElement(this.locators.removeButtonForInvitee(invitee))
        .click();
    }

    toggleNonRespondersVisibility() {
        this.driver.findElement(this.locators.toggleNonRespondersVisibility)
        .click();
    }
}

module.exports = HomePage;