Add coverage xml to CI artifacts
cc @npond, we need to modify something here https://gitlab.cern.ch/atlas-flavor-tagging-tools/algorithms/salt/-/blob/main/.gitlab/.ci-coverage.yaml?ref_type=heads#L9
cc @npond, we need to modify something here https://gitlab.cern.ch/atlas-flavor-tagging-tools/algorithms/salt/-/blob/main/.gitlab/.ci-coverage.yaml?ref_type=heads#L9