Update from javax.servlet to jakarta.servlet

[adam-long]

In Java 11, the javax.servlet package was removed. Servlet support has moved to the Eclipse Foundation with a package name of jakarta.servlet. The references to javax.servlet should be updated for compatibility with Tomcat versions 10 and newer.

[jodygarnett]

This is a much larger activity then just changing the API as we must update to spring-framework-6.

To support this activity please see https://geoserver.org/behind%20the%20scenes/2024/09/10/gs3.html