Check for a behavior change on the getServerInfo method

This rule flags references to the javax.servlet.ServletContext.getServerInfo() method because the Servlet 3.1 feature implementation returns a different value. In Servlet 3.0, this method returns SMF WebContainer. In Servlet 3.1, this method returns IBM WebSphere Liberty/8.5.5.<x>, where <x> is the fix pack number. The <x> indicates that the value changes as the server that runs the application is updated. For more information about this method, see Interface ServletContext.

For more information on Servlet 3.1 behavior changes, see the following resource: Servlet 3.1 behavior changes.