We can create ghost commit on iceberg and push them

[AntoninGoslin]

While working on a project, I found a weird bug that causes us to push some commits on GitHub that are empty.
Here is a simple way to reproduce:

1. Go on a random project and do a modification
2. Go on Iceberg and open the commit windows on it
3. Deselect the actual class where modifications appear and write a comment

4. You can commit without involving any code

This bug is not working when you don't select any package, but it works when you select at least one and don't select anything in it