[`pandas-vet`] Remove `pandas-df-variable-name` (`PD901`) (#19223)
## Summary
closes #7710
## Test Plan
It is is removal so i don't think we have to add tests otherwise i have
followed test plan mentioned in contributing.md
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Co-authored-by: Brent Westbrook <36778786+ntBre@users.noreply.github.com>
