Cannot change version of project facet Dynamic Web Module to 3.0?

I updated my web.xml

<web-app xmlns="http://java.sun.com/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
          http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
    version="3.0">
    <display-name>Servlet 3.0 Web Application</display-name>
</web-app>

and then just Maven -> Update Project ...

Another way is to edit the project facet configuration file itself: org.eclipse.wst.common.project.facet.core.xml

Change the dynamic web module version in this line to 3.0 - <installed facet="jst.web" version="2.5"/>

And then:

1. Right-click on the project (in the Project Explorer panel).
2. Select Maven » Update Project (or press Alt+F5)

You'll find this file in the .settings directory within the Eclipse project.