`nimble test -c` always returns success exit code `0` even on fail
### Received Output
```sh
Error: Only 2/3 tests passed
$ echo $?
0
```

### Expected Output
```sh
Error: Only 2/3 tests passed
$ echo $?
1
```

Basically, if any tests fail, I would expect the exit code to be 1, whether the continue/c flag is passed or not.