Only omit optinal parens if the expression ends or starts with a parenthesized expression
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## Summary
This PR matches Black' behavior where it only omits the optional parentheses if the expression starts or ends with a parenthesized expression:
```python
a + [aaa, bbb, cccc] * c # Don't omit
[aaa, bbb, cccc] + a * c # Split
a + c * [aaa, bbb, ccc] # Split
```
<!-- What's the purpose of the change? What does it do, and why? -->
## Test Plan
This improves the Jaccard index from 0.945 to 0.946
ruff
30bec3fc - Only omit optinal parens if the expression ends or starts with a parenthesized expression
