[`flake8-simplify`] Implement fix for `maxsplit` without separator (`SIM905`) (#19851)
**Stacked on top of #19849; diff will include that PR until it is
merged.**
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## Summary
As part of #19849, I noticed this fix could be implemented.
## Test Plan
Tests added based on CPython behaviour.
ruff
2e1d6623 - [`flake8-simplify`] Implement fix for `maxsplit` without separator (`SIM905`) (#19851)
