Format error

```
cpk| INFO : Parameter `arch` not given, will resolve it from the endpoint.
cpk| INFO : Parameter `arch` automatically set to `amd64`.
cpk| INFO : Running an image for amd64 on amd64.
cpk| INFO : Working with an `amd64` image on `amd64`. Multiarch not needed!
Traceback (most recent call last):
File "/home/afdaniele/.local/bin/cpk", line 6, in
run()
File "/home/afdaniele/.local/lib/python3.8/site-packages/cpk/cli/main.py", line 66, in run
command.execute(machine, parsed)
File "/home/afdaniele/.local/lib/python3.8/site-packages/cpk/cli/commands/run.py", line 280, in execute
raise ValueError("You cannot use the option --launcher together with --cmd.")
ValueError: You cannot use the option --launcher together with --cmd.
```