Update graph_utils.py

[moresearch]

Adds export_path for visualize_speaker_transitions_dict

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[joshkyh]

Thanks for coming back with a PR.

Given the 90+% overlap with visualize_speaker_transitions_dict, I'd suggest adding a export_path:str which defaults to None into visualize_speaker_transitions_dict. In there, run plt.savefig(path) if export_path is not None

[joshkyh]

Thank you @moresearch. Looks good to me! :)

[joshkyh]

Hey @moresearch, a tip to run pre-commit run --all-files on the root folder of the Autogen dev container to pass
Code formatting / pre-commit-check (pull_request) Failing after 41s

[moresearch]

Thanks for the tip @joshkyh

[joshkyh]

Looks good to me, and non-llm tests are passing. Perhaps good to merge, @ekzhu?