Upgrades ipynbdiff to 0.4.4

What does this MR do and why?

On !75500 (merged) we introduced changes to how ipynb diffs are displayed, which caused a performance degradation. This MR introduces the changes seen in gitlab-org/incubation-engineering/mlops/rb-ipynbdiff!12 (merged) that help mitigating the issue. Further optimisations are being worked on, but meanwhile we will ship current improvements.

How to set up and validate locally

1. Import https://gitlab.com/kroseaf/notebook-diff-viewer into your GDK instance
2. Create a Merge Request from new-notebook into main
3. Without the changes, the MR will not load, and will timeout (looking at the network tab on the developer console, you will see diffs_metadata.json will return a 500)
4. With the changes the MR now loads

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.