Integrate gitlab-ci/update-container-images and 2 more

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Commit: clea-os/infrastructure/gitlab-ci@12d0d7d2

[DOCKER] Hardcode the tag for clea-os-builder Docker image

It follows the different tagging scheme, so might break if we
change the CI_IMAGES_REV for images from gitlab registry

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Commit: clea-os/infrastructure/gitlab-ci@ca1a2d56

[DOCKER] Add variable for LAVA an Exein Docker images

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Commit: clea-os/infrastructure/gitlab-ci@91fe9a6d

[DOCKER] Adopt new Docker images url scheme