Avoid extra parentheses in unary expressions (#7428)
## Summary
This PR applies a similar fix to unary expressions as in
https://github.com/astral-sh/ruff/pull/7424. Specifically, we only need
to parenthesize the entire operator if the operand itself doesn't have
parentheses, and requires parentheses.
Closes https://github.com/astral-sh/ruff/issues/7423.
## Test Plan
`cargo test`
No change in similarity.
Before:
| project | similarity index | total files | changed files |
|--------------|------------------:|------------------:|------------------:|
| cpython | 0.76083 | 1789 | 1632 |
| django | 0.99982 | 2760 | 37 |
| transformers | 0.99957 | 2587 | 399 |
| twine | 1.00000 | 33 | 0 |
| typeshed | 0.99983 | 3496 | 18 |
| warehouse | 0.99923 | 648 | 18 |
| zulip | 0.99962 | 1437 | 22 |
After:
| project | similarity index | total files | changed files |
|--------------|------------------:|------------------:|------------------:|
| cpython | 0.76083 | 1789 | 1632 |
| django | 0.99982 | 2760 | 37 |
| transformers | 0.99957 | 2587 | 399 |
| twine | 1.00000 | 33 | 0 |
| typeshed | 0.99983 | 3496 | 18 |
| warehouse | 0.99923 | 648 | 18 |
| zulip | 0.99962 | 1437 | 22 |
