Vaadin Framework 7 with Spring boot using Flow

Question

I have a legacy Spring Vaadin 7 application what runs on Weblogic as a war.

Since just to redeploy takes like 10 minutes, I want to Use Spring boot with embedded Tomcat.

Following This example I can run the application. https://vaadin.com/docs/v14/flow/integrations/spring/tutorial-spring-basic

Now my problem is that my application uses VerticalLayout from com.vaadin.flow.component.orderedlayout.VerticalLayout and my VerticalLayout is from Vaadin 7.

    @Route
    public class MainView extends VerticalLayout {
    
        public MainView() {
            add(new Text("Welcome to MainView."));
        }
    }

Is it possible to use the com.vaadin.flow.component.orderedlayout.VerticalLayout with Vaadin 7 components? (Like an Adapter, a post construct setting, anything....)

I've only found some suggestions to use Spring boot 1.X...that would be fine with me but I've not found a repository what I could run easily and add my Vaadin 7 UI components.