Unquoted '{key: value}' in a GitHub Actions run line breaks the whole workflow

A step like run: uv run dbt build --vars '{bronze_schema: candyops}' is invalid YAML: the plain scalar contains ': ', so GitHub rejects the entire workflow file (the run is named after the file path and fails in seconds with 'This run likely failed because of a workflow file issue'). Any downstream workflow_run deploy is then skipped. Quote the whole command (run: "... --vars '{k: v}'") or use a block scalar. Run actionlint (e.g. nix run nixpkgs#actionlint -- .github/workflows/*.yml) before pushing; it reports 'mapping values are not allowed in this context' with the column.