We need to update the version of Docling in the main branch (1.5) to address RHELAI-3653 a critical error that impacts document conversion for markdown documents in our synthetic data generation pipeline.
Please refer to the upstream PR: https://github.com/instructlab/sdg/pull/583 , which shows how the requirements.txt was modified to pull in the newer Docling version.

[AC]
Ensure compatibility with the 1.5 base and validate with synthetic data tests.