Updating notebook for more elaborate tutorial 📔

[KristinaUlicna]

PR summary:

Changes to the ctc.ipynb notebook to:

• Detection of certificate error - closes [BUG] Downloading GT data for ctc.ipynb throws an [SSL: CERTIFICATE_VERIFY_FAILED] URLError #84
• Instruct the user on how to manually resolve ⬆️ - closes [DOCS] Update ctc.ipynb notebook with note about [SSL: CERTIFICATE_VERIFY_FAILED] #102
• Instantiate the TrackingGraph upon each computation to avoid maintenance of previously computed attributes with tracking_graph_data_loader mini function hack - resolved [BUG] IOUMatched with various IoU thresholds not reflected in metrics #101
• Compute the metrics with moving IoU threshold to monitor the metrics / performance dependence ▶️ visualised on a plot 🎨 Closes [VIZ] Plot the dependence of metric value on IoU threshold for matching #106

What should the reviewer focus their feedback on?

• Overall sanity check (motivation behind the plot)
• Code documentation / annotation quality

[msschwartz21]

This is a nice first upgrade! A few initial thoughts

• Can we clear the error message output from the download cell?
• The issue that necessitated the tracking_graph_data_loader will be fixed in Refactor existing Matched into separate Matcher which returns Matched #103 so I would like to maybe wait for that PR and then update this notebook accordingly.
• Can we add back a non-zero frame buffer value in at least one case of the division metrics?

[KristinaUlicna]

Ofc, implementing rn! Thanks for the suggestions @msschwartz21 👍