LTWebsiteTest.php

<?php
require 'vendor/autoload.php';
 
use PHPUnit\Framework\TestCase;
use Facebook\WebDriver\Remote\DesiredCapabilities;
use Facebook\WebDriver\Remote\RemoteWebDriver;
use Facebook\WebDriver\WebDriverBy;
 
$GLOBALS['LT_USERNAME'] = "user-name";
# accessKey:  AccessKey can be generated from automation dashboard or profile section
$GLOBALS['LT_APPKEY'] = "access-key";
 
class LTWebsiteTest extends TestCase
{
  protected $webDriver;
  
  public function build_browser_capabilities(){
    /* $capabilities = DesiredCapabilities::chrome(); */
    $capabilities = array(
      "build" => "[PHP] Test-3 on IE and Windows 10",
      "name" => "[PHP] Test-3 on IE and Windows 10",
      "platform" => "Windows 10",
      "browserName" => "Internet Explorer",
      "version" => "11.0",
      "ie.compatibility" => 11001
    );
    return $capabilities;
  }
  
  public function setUp(): void
  {
    $capabilities = $this->build_browser_capabilities();
    /* Download the Selenium Server 3.141.59 from 
    https://selenium-release.storage.googleapis.com/3.141/selenium-server-standalone-3.141.59.jar
    */
    $url = "https://". $GLOBALS['LT_USERNAME'] .":" . $GLOBALS['LT_APPKEY'] ."@hub.lambdatest.com/wd/hub";
    $this->webDriver = RemoteWebDriver::create($url, $capabilities);
  }
 
  public function tearDown(): void
  {
    $this->webDriver->quit();
  }
  /*
  * @test
  */ 
  public function test_LT_Blog()
  {
    $expected_title = "Most Powerful Cross Browser Testing Tool Online | LambdaTest";
 
    $this->webDriver->get("https://www.google.com/ncr");
    $this->webDriver->manage()->window()->maximize();
    
    sleep(5);
    
    $element = $this->webDriver->findElement(WebDriverBy::name("q"));
    if($element) {
      $element->sendKeys("LambdaTest");
      $element->submit();
    }
 
    /* Click on the first result */
    $search_result = $this->webDriver->findElement(WebDriverBy::Xpath("//h3[.='LambdaTest: Most Powerful Cross Browser Testing Tool Online']"));
    $search_result->click();
    sleep(5);
 
    print $this->webDriver->getTitle();
    $this->assertEquals($expected_title, $this->webDriver->getTitle());
 
    print "Test Completed";
  }
}
?>

According to the official PHPUnit doc, it should be protected function setUp(): void and protected function tearDown(): void methods.