RFE: descriptions for tests run via kola

[miabbott]

Some folks on the CoreOS team are trying to better understand what kind of tests we have for FCOS/RHCOS and where we have opportunity to grow our coverage. The first step is documenting the existing tests and what use cases they cover.

Right now that is a bit more work as we have to enumerate the tests via kola list, find the "other" kola tests like kola run-upgrade and kola testiso, then dig into the code to understand what exactly they are testing.

I'd like to float the idea of a description field for all the tests that could be used to clearly describe what the test is trying to do. Ideally, it is a one-line summary, but multi-line strings seem like something we would need to support.

Then someone could run kola list --describe and they would get the one'ish-line description of the test.

Imagined example:

$ kola list --describe | head
Test Name                                                       Description 

basic                                                           Tests basic functionality like SSH, systemd services, useradd, etc
coreos.auth.verify                                              Verifies that incorrect passwords prevent access to the host
coreos.boot-mirror                                              Verifies that using RAID1 for the boot disk is successful
coreos.boot-mirror.luks                                         Verifies that using RAID1 + LUKS for the boot disk is successful
coreos.ignition.failure                                         Tests that Ignition fails correctly 
coreos.ignition.groups                                          Verifies that Ignition can create groups
coreos.ignition.instantiated.enable-unit                        Verifies that Ignition can enable systemd units
coreos.ignition.journald-log                                    Verifies that Ignition can write logs to the journal

This would also allow newcomers to the project to better understand the tests available.