exec < /dev/tty && make an error?

``` javascript
module.exports = {
"hooks": {
// "prepare-commit-msg": "echo foooooo", // it works
"prepare-commit-msg": "exec < /dev/tty && echo foooooo",
}
}
```

With the config above in `.huskyrc.js`, I will get an error in console:
```
husky > prepare-commit-msg (node v10.11.0)
The system cannot find the path specified.
husky > prepare-commit-msg hook failed (cannot be bypassed with --no-verify due to Git specs)
```

What's the cause?