CI: Enable bare metal testing for Ubuntu upgrades

More than one year ago, change I96827fc32c1594ca9a0535e259929c49d3f0e704
enabled bare metal testing on Ubuntu, but only for non-upgrade jobs. It
should be safe to test during upgrade jobs too.

Change-Id: I9c698916999b30bf3fd8f7dfe5add7d332a84b6c