loadbalancer subscriber creation panic

## Description:

## How to reproduce:
```scw lb subscriber create name="test-dev"```
### Command attempted

### Expected Behavior

### Actual Behavior

## More info

## Version

Version    2.18.0
BuildDate  unknown
GoVersion  go1.20.6
GitBranch  unknown
GitCommit  unknown
GoArch     amd64
GoOS       darwin
