When a Jetty 12 Jenkins test harness is used (i.e., one built from the prototype branch of jenkins-test-harness), the following tests fail:

• org.jenkinsci.plugins.GithubAccessTokenPropertySEC797Test
• org.jenkinsci.plugins.GithubAccessTokenPropertyTest

This is just a trivial matter of changing the import package from org.eclipse.jetty.servlet to org.eclipse.jetty.ee8.servlet. Unfortunately, this is not backward compatible with Jetty 10, so the PR will have to remain in draft until we release JTH with Jetty 12 support. Still, we should prepare the PR in advance.