`date -f - "+%Y-%m-%d %r"` is failing

Coreutils
```shell
$/target/debug/coreutils date -f - "+%Y-%m-%d %r"
date: -: No such file or directory 
``` 
GNU 
```shell
$date -f - "+%Y-%m-%d %r"
2023-04-15 18:30:00
2023-04-15 06:30:00 PM 
``` 

It seems `date -f -` doesn't take input from stdin when invoked with `-f -` like is mentioned in the GNU documentation.
