Always reset iterator state

[freddyaboulton]

Description

Iterators were only reset if the process finished - which can cause memory problems if the iterators create a lot of memory and users close the client before termination.

Context: https://huggingface.slack.com/archives/C051XU5MGTD/p1680704644172439

Checklist:

• I have performed a self-review of my own code
• I have added a short summary of my change to the CHANGELOG.md
• My code follows the style guidelines of this project
• I have commented my code in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

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[gradio-pr-bot]

All the demos for this PR have been deployed at https://huggingface.co/spaces/gradio-pr-deploys/pr-3777-all-demos

[abidlabs]

Nice @freddyaboulton! PR and test look good, and good to know that we have confirmation that it fixed the issue for the user.

[freddyaboulton]

Thanks for the review @abidlabs !