Add ability to increase default timeout for BrowserWebDriverContainer when checking if it's started

Hi, seems that on some slow agents we might be hitting the 30s hardcoded timeout. While we can extend BrowserWebDriverContainer to override containerIsStarted() (it's not perfect though since we cannot just copy paste the default content as it uses some private variables), it would be even nicer if the timeout could be configurable.

I'm referring to:

    protected void containerIsStarted(InspectContainerResponse containerInfo) {
        this.driver = (RemoteWebDriver)Unreliables.retryUntilSuccess(30, TimeUnit.SECONDS, (Callable)Timeouts.getWithTimeout(10, TimeUnit.SECONDS, () -> {
            return () -> {
                return new RemoteWebDriver(this.getSeleniumAddress(), this.capabilities);
            };
        }));
        if (this.vncRecordingContainer != null) {
            LOGGER.debug("Starting VNC recording");
            this.vncRecordingContainer.start();
        }

    }

What I did FTR:

public class XWikiBrowserWebDriverContainer<T extends BrowserWebDriverContainer<T>> extends BrowserWebDriverContainer<T>
{
    private Capabilities capabilities;

    @Override
    protected void containerIsStarted(InspectContainerResponse containerInfo)
    {
        Unreliables.retryUntilSuccess(60, TimeUnit.SECONDS,
            Timeouts.getWithTimeout(20, TimeUnit.SECONDS,
                () -> () -> new RemoteWebDriver(this.getSeleniumAddress(), this.capabilities)));
        super.containerIsStarted(containerInfo);
    }

    @Override
    public T withCapabilities(Capabilities capabilities)
    {
        this.capabilities = capabilities;
        return super.withCapabilities(capabilities);
    }
}

Thanks!

Start with BrowserWebDriverContainer.containerIsStarted and the retry and driver-creation path shown in the issue. Trace how withCapabilities and the private state are used, then locate the existing container startup tests before making the timeout configurable. Done means slow agents can override the startup wait without copying private implementation details.