To Reproduce Steps to reproduce the behavior:

Deploy RHEL AI 1.4.x onto a server with enough resources to complete the SDG run, initializing ilab correctly

Error reproduced by Ben for the document shared by rhn-support-jharmiso :

 File "/home/bbrownin/tmp/docling-index-out-of-range/venv/lib/python3.11/site-packages/docling/pipeline/simple_pipeline.py", line 41, in _build_document
    conv_res.document = conv_res.input._backend.convert()
                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/bbrownin/tmp/docling-index-out-of-range/venv/lib/python3.11/site-packages/docling/backend/md_backend.py", line 340, in convert
    self.iterate_elements(parsed_ast, 0, doc, None)
  File "/home/bbrownin/tmp/docling-index-out-of-range/venv/lib/python3.11/site-packages/docling/backend/md_backend.py", line 306, in iterate_elements
    self.iterate_elements(child, depth + 1, doc, parent_element)
  File "/home/bbrownin/tmp/docling-index-out-of-range/venv/lib/python3.11/site-packages/docling/backend/md_backend.py", line 166, in iterate_elements
    f" - Heading level {element.level}, content:

"
                                                  ~~~~~~~~~~~~~~~~^^^
IndexError: list index out of range

Error arising from older docling version. 

Expected behavior

• SDG pipeline should run successfully

Device Info (please complete the following information):

• • All/Any

Bug impact

• Any time user tries md files with unescaped special characters that imply special markdown handling, such as * to indicate an unordered list item or # to indicate a header block, with no following content sdg will fail.

Known workaround

• avoid unescaped special characters in md
• Ben proposed   - Avoid empty markdown headings by themselves for the document shared by field teams containing those characters. https://github.com/DS4SD/docling/pull/843