[libcxx-commits] [libcxx] Fix capacity increase issue with `shrink_to_fit` for `__split_buffer` (PR #117720)

[Louis Dionne via libcxx-commits]

https://github.com/ldionne approved this pull request.

This makes sense to me. It's not user-visible, but if `deque::shrink_to_fit()` aims to never increase the capacity, it feels like also doing the same for `__split_buffer` follows the design intent of `deque::shrink_to_fit()` better.

https://github.com/llvm/llvm-project/pull/117720