Fix Studio hotreload when branch management activated

During several hotreloads of a Studio bundle with different branches, Nuxeo is not removing the previous bundle from the previous branch:

• Go to master branch in studio
• Hotreload the current studio bundle on the platform
• Go to another branch in studio
• Hotreload this new studio bundle on the platform
• Check bundles folder content -> 2 studio bundles are present

This bug appears to occur regularly on Windows but randomly on other OS.

On windows, if I recall, to force remove a file used by a process -> move then remove.