Upgrade pypdf to 6.9.1 due to CVE.

[alexaryn]

No description provided.

[blacksmith-sh]

Found 23 test failures on Blacksmith runners:

Failures

Test	View Logs
test_cached_anthropic_different_models	View Logs
test_pdf_to_opensearch_with_llm_caching	View Logs
test_pinecone_read	View Logs
test_qdrant	View Logs
test_qdrant_named_vector	View Logs
test_sycamore_batched	View Logs
test_to_neo4j	View Logs
/home/runner/_work/sycamore/sycamore/notebooks/ArynPartitionerPython/ipynb	View Logs
/home/runner/_work/sycamore/sycamore/notebooks/docprep/ minilm-l6-v2_greedy-section-merger_opensearch/ipynb	View Logs
test_aryn_reader_with_original_elements[ExecMode/LOCAL]	View Logs
test_aryn_reader_with_original_elements[ExecMode/RAY]	View Logs
TestOpenSearchRead/test_result_filter_on_property_knn	View Logs
TestPaddleOcr/test_paddle_ocr_on_pdf	View Logs
TestSycamoreQuery/test_dry_run[False]	View Logs
TestSycamoreQuery/test_dry_run[True]	View Logs
TestSycamoreQuery/test_forked[False]	View Logs
TestSycamoreQuery/test_forked[True]	View Logs
TestSycamoreQuery/test_simple[False]	View Logs
TestSycamoreQuery/test_simple[True]	View Logs
TestSycamoreQuery/test_simple_with_result_filter[False]	View Logs
TestSycamoreQuery/test_vector_search_2	View Logs
TestSycamoreQuery/test_vector_search_3	View Logs
TestSycamoreQuery/test_vector_search_with_result_filter[False]	View Logs