Auto merge of #27994 - teymour-aldridge:fix-divide-by-zero, r=emilio

Fix num_threads to avoid divide by zero error when running without a thread pool

Signed-off-by: teymour-aldridge <teymour.aldridge@icloud.com>

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This updates the style thread pool to set `num_threads` to `None` rather than `0` when running without a thread pool.

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- [ ] These changes fix #___ (GitHub issue number if applicable)

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I *think* this change might not need tests, but if it does I'm not sure exactly how to do so.

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0 files changed, 0 insertions, 0 deletions