test: print slowest unittests (#1911)
Show which tests are slowing things down when running `make test`:
E.g., from the CI run in this PR:
```
2023-10-27T05:51:05.6256039Z 105.12s setup test_unstructured/partition/pdf_image/test_pdf.py::test_chipper_has_hierarchy
2023-10-27T05:51:05.6257784Z 93.47s call test_unstructured/partition/pdf_image/test_pdf.py::test_partition_pdf_hi_res_ocr_mode_with_table_extraction[entire_page]
2023-10-27T05:51:05.6259866Z 93.09s call test_unstructured/partition/pdf_image/test_pdf.py::test_partition_pdf_hi_res_ocr_mode_with_table_extraction[individual_blocks]
2023-10-27T05:51:05.6261818Z 31.70s call test_unstructured/partition/epub/test_epub.py::test_add_chunking_strategy_on_partition_epub_non_default
2023-10-27T05:51:05.6263774Z 17.22s call test_unstructured/partition/pdf_image/test_pdf.py::test_partition_pdf[hi_res-expected1-pdf-filename]
2023-10-27T05:51:05.6265658Z 17.13s call test_unstructured/partition/pdf_image/test_pdf.py::test_partition_pdf[hi_res-expected1-pdf-spool]
2023-10-27T05:51:05.6273195Z 16.95s call test_unstructured/partition/pdf_image/test_image.py::test_add_chunking_strategy_on_partition_image_hi_res
2023-10-27T05:51:05.6275118Z 16.77s call test_unstructured/partition/pdf_image/test_pdf.py::test_partition_pdf[hi_res-expected1-pdf-rb]
2023-10-27T05:51:05.6276759Z 14.64s call test_unstructured/partition/test_text.py::test_partition_text_detects_more_than_3_languages
2023-10-27T05:51:05.6278381Z 13.86s call test_unstructured/partition/pdf_image/test_image.py::test_partition_image_with_multipage_tiff
2023-10-27T05:51:05.6280137Z 13.51s call test_unstructured/partition/test_auto.py::test_auto_partition_pdf_from_filename[False-None]
2023-10-27T05:51:05.6281995Z 13.41s call test_unstructured/partition/test_html_partition.py::test_add_chunking_strategy_on_partition_html
2023-10-27T05:51:05.6283640Z 12.80s call test_unstructured/partition/pdf_image/test_pdf.py::test_partition_pdf_with_copy_protection
2023-10-27T05:51:05.6285305Z 12.46s call test_unstructured/partition/pdf_image/test_image.py::test_add_chunking_strategy_on_partition_image
2023-10-27T05:51:05.6287250Z 12.39s call test_unstructured/partition/pdf_image/test_image.py::test_partition_image_hi_res_ocr_mode_with_table_extraction[individual_blocks]
2023-10-27T05:51:05.6289347Z 12.14s call test_unstructured/partition/pdf_image/test_pdf.py::test_partition_pdf_from_file_with_hi_res_strategy_custom_metadata_date
2023-10-27T05:51:05.6291329Z 12.12s call test_unstructured/partition/pdf_image/test_pdf.py::test_partition_pdf_with_hi_res_strategy_custom_metadata_date
2023-10-27T05:51:05.6293388Z 12.12s call test_unstructured/partition/test_auto.py::test_auto_partition_pdf_from_file[True-application/pdf]
2023-10-27T05:51:05.6294869Z 12.08s call test_unstructured/partition/test_auto.py::test_auto_with_page_breaks
2023-10-27T05:51:05.6296396Z 12.02s call test_unstructured/partition/pdf_image/test_pdf.py::test_partition_pdf_with_hi_res_strategy_metadata_date
2023-10-27T05:51:05.6298278Z 11.99s call test_unstructured/partition/pdf_image/test_pdf.py::test_partition_pdf_from_file_with_hi_res_strategy_metadata_date
```
