Avoid nested quotations in auto-quoting fix (#9168)
## Summary
Given `Callable[[Callable[_P, _R]], Callable[_P, _R]]` from the
originating issue, when quoting `Callable`, we quoted the inner
`[Callable[_P, _R]]`, and then created a separate edit for the outer
`Callable`. Since there's an extra level of nesting in the subscript,
the edit for `[Callable[_P, _R]]` correctly did _not_ expand to the
entire expression. However, in this case, we should discard the inner
edit, since the expression is getting quoted by the outer edit anyway.
Closes https://github.com/astral-sh/ruff/issues/9162.