Integrate gitlab-ci/include-not-found-message and 1 more

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Commit: seco-ne/yocto/infrastructure/gitlab-ci@ed36b465

mirror_mr_pipeline: include pipeline-not-found message in output

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Commit: seco-ne/yocto/infrastructure/gitlab-ci@5ee69ab9

mirror_mr_pipeline: fix error when no pipeline found

This case should trigger a new pipeline instead of reporting an error.