PDFx test for sample-flyer.pdf

Input: sample-flyer.pdf

(cd "sample-flyer.pdf_dir" && uv run --project "$repo_root" pdfx -t "sample-flyer.pdf_name" -o "sample-flyer--pdfx-python.txt")

(cd "sample-flyer.pdf_dir" && uv run --project "$repo_root" pdfx -j "sample-flyer.pdf_name" -o "sample-flyer--pdfx-python.json")