Integrate gitlab-ci/share-build-and-test-job-basics

--

Commit: seco-ne/yocto/infrastructure/gitlab-ci@075aeccb

Refactoring: share build and test job basics for ci-test and Yocto

This shares YAML code for the following procedures:
- Build environment
- Source code checkout via repo
- SSH key and known hosts setup
- LAVA test submission
- Docker check if build folder is empty