Hello Rehman, you can disable Developer Mode Extension in Chrome by using ChromeOptions. Use following lines of code to disable it:
//Set the chrome path
System.setProperty("webdriver.chrome.driver", "C:\\Users\\Anvi_R\\Downloads\\ChromeDriver\\chromedriver.exe");
// Create object of ChromeOptions class
ChromeOptions options = new ChromeOptions();
// add parameter which will disable the extension
options.addArguments("--disable-extensions");
// Start the chrome session
WebDriver driver = new ChromeDriver(options);