Jammy (22.04) CI

[Baltoli]

This PR makes several changes to the K CI scripts in preparation for the Bionic / Jammy switch:

• Ubuntu Focal is made the primary CI distribution on which the full K exercises test suite is run, replacing Bionic.
• Jammy is added as an extra variant to the set of distributions on which we build release packages; recent changes to dpkg mean that jammy-specific options need to be passed when building .deb packages.

Important notes for this PR:

• Bionic is not yet removed from the CI scripts; this needs to follow a separate audit of downstream projects.
• As written, the Jenkins rules in this PR run more work on each new PR. This is to make sure that Bionic, Focal and Jammy all work without having to attempt a merge to master. This PR should be followed up immediately by a separate PR that undoes this change, and only runs all three versions on master.

[dwightguth]

looks okay, needs some minor improvements.

[radumereuta]

I'm going to let Dwight review this since he seems more knowledgeable than I am.