Avoid extra parentheses in `await` expressions (#7424)
## Summary
This PR aligns the await parenthesizing with the unary case, which is:
if the value is already parenthesized, avoid parenthesizing; otherwise,
only parenthesize if the _value_ needs parenthesizing.
Closes https://github.com/astral-sh/ruff/issues/7420.
## 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 |
