[pkg] return better error in case of device offline in adb

It seems that adb lost connection to the device and cannot re-establish if the server is closed for whatever reason. You can reproduce it by
```
adb shell
adb kill-server
adb shell
```

We should, for start, be able to return [here](https://github.com/arduino/arduino-app-cli/blob/main/pkg/board/remote/adb/adb.go) a clear error if we cannot execute commands for this reason.