remove definitely useless parentheses

[mvdan]

Some examples:

chan (int)
f((3))

We don't want to do this in all cases where a parentheses is unambiguous, though. For example, within binary expressions like (foo && bar) && baz it can help readability and maintainability, even if the parentheses don't actually change the evaluation.

[twpayne]

Relevant discussion: https://github.com/go-critic/go-critic/issues/836

[ashn4455]

Thanks so much🩺

[doubbz]

I can work on this if you like