`cro3 dut list --add` eats input stream

When I tried to inport DUT address list from stdin like;
```
cat duts.txt | while read addr; do cro3 dut list --add $addr; done
```
This command exited unexpectedly after inported the 1st entry.
I could fixed it by adding `< /dev/null` to the cro3 command.
```
cat duts.txt | while read addr; do cro3 dut list --add $addr < /dev/null ; done
```
But this means `cro3 dut list --add` ate all input from standard input.