Fix T50954: Improve Blender Cloud add-on project selector

Attract and Flamenco features are (de)activated based on the extensions
enabled on the selected project. As a result, anyone can use the add-on
again, without seeing Attract or Flamenco things they can't use.

blender_cloud/__init__.py

@@ -94,6 +94,8 @@ def register():
     image_sharing.register()
     attract.register()
 
+    blender.handle_project_update()
+
 
 def _monkey_patch_requests():
     """Monkey-patch old versions of Requests.