Can't start Xcode - stuck on installing state I was trying to upgrade Xcode because it didn't let me upload to apps to iTunes Connect.

Now it's stuck in installing state (few hours) and doesn't start:

Xcode is being updated 
Xcode can not be opened while it is being updated.


what do to?
There is a small progress bar under the Launchpad icon in the Menu Bar.



You can also see the current download progress by hovering over the icon.

Wait for it to end.