lava: Merge the job templates from apertis-tests

Keeping the LAVA job templates in `apertis-tests` has many problems.

Since `apertis-tests` is also a package, updates for stable releases
should go through `-updates` branches, but that plays badly with the
image building recipes as they only pull from the the main branch.

There's also an annoying disconnect about what the testcases here say
about where they should be run, and the actual groups used by the
templates.

By moving the LAVA templates here we can later improve them by
generating the groups based on the actual data in the testcases.

Signed-off-by: Emanuele Aina <emanuele.aina@collabora.com>