Просто введите этот код для скриншота.
ExtentTestManager.startTest(method.getName(), description);
ExtentTest extentTest = ExtentTestManager.getTest();
String base64Screenshot = "data:image/png;base64," + ((TakesScreenshot) driver).getScreenshotAs(OutputType.BASE64);
extentTest.log(LogStatus.FAIL, logs, ExtentTestManager.getTest().addBase64ScreenShot(base64Screenshot));