Fix silent failure in BrowserWebDriverContainer#getSeleniumAddress

[dev-xong]

Fix silent failure in BrowserWebDriverContainer#getSeleniumAddress

What does this PR do?

Fixed the // TODO left in BrowserWebDriverContainer#getSeleniumAddress().

The existing code caught MalformedURLException and only called e.printStackTrace(), returning null:

public URL getSeleniumAddress() {
    try {
        return new URL("http", getHost(), getMappedPort(SELENIUM_PORT), "/wd/hub");
    } catch (MalformedURLException e) {
        e.printStackTrace(); // TODO
        return null;
    }
}

This PR wraps the exception in ContainerLaunchException and throws it immediately, matching the existing error-handling pattern already used elsewhere in this class (e.g. for temp directory creation failures):

public URL getSeleniumAddress() {
    try {
        return new URL("http", getHost(), getMappedPort(SELENIUM_PORT), "/wd/hub");
    } catch (MalformedURLException e) {
        throw new ContainerLaunchException("Could not construct Selenium address", e);
    }
}

The identical duplicated code in org.testcontainers.selenium.BrowserWebDriverContainer is fixed the same way.