[`ruff`] Fix UP032 conversion for decimal ints with underscores (#21022)
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Fixes #21017
Taught UP032’s parenthesize check to ignore underscores when inspecting
decimal integer literals so the converter emits `f"{(1_2).real}"`
instead of invalid syntax.
## Test Plan
Added test cases to UP032_2.py.
<!-- How was it tested? -->
ruff
6c18f184 - [`ruff`] Fix UP032 conversion for decimal ints with underscores (#21022)
