forked from extern/nushell
A partial fix for #7477. `uniq` can be slow sometimes, so we should check `ctrl-c` when it's running. Tested on [this file](https://home.treasury.gov/system/files/276/yield-curve-rates-1990-2021.csv), I ran `open yield-curve-rates-1990-2021.csv | uniq` and confirmed that I can now cancel the operation. Future work is needed to figure out why `uniq` is so slow.