[`flake8-comprehensions`] Handle extraneous parentheses around list comprehension (`C403`) (#15877)
## Summary
Given the following code:
```python
set(([x for x in range(5)]))
```
the current implementation of C403 results in
```python
{(x for x in range(5))}
```
which is a set containing a generator rather than the result of the
generator.
This change removes the extraneous parentheses so that the resulting
code is:
```python
{x for x in range(5)}
```
## Test Plan
`cargo nextest run` and `cargo insta test`