fetch-artifact docstring

pixi.toml

@@ -179,6 +179,9 @@ upload-image = "python scripts/upload_image.py"
 # Check whether there's too large files in the repository.
 check-large-files = "python scripts/ci/check_large_files.py"
 
+# Download a specific artifact from gcloud.
+#
+# Requires that gcloud authentication has already been set up in your shell.
 fetch-artifact = "python scripts/ci/fetch_artifact.py"
 
 [feature.py-docs.tasks]