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.

This goes hand-in-hand with infrastructure/apertis-image-recipes!243 (merged)