Show build error if spine scene can't be loaded

[AGulev]

If there is no image in atlas which needed for spine scene it shows an error only in scene:

But the game builds and exits when it's trying to load such a scene :

INFO:ENGINE: Initialised sound device 'default'
ERROR:SPINEC: Failed to read spine skeleton for /assets/coins/coin.spinescenec: (null)
WARNING:RESOURCE: Unable to create resource: /assets/coins/coin.spinescenec: INVALID_DATA
WARNING:RESOURCE: Unable to create resource: /_generated_3b7dfa95.spinemodelc: INVALID_DATA
WARNING:RESOURCE: Unable to create resource: /_generated_e2b44320.goc: INVALID_DATA
ERROR:GAMEOBJECT: Could not instantiate game object from prototype /_generated_e2b44320.goc.
WARNING:RESOURCE: Unable to create resource: /main/main.collectionc: FORMAT_ERROR
INFO:DEFOLDIMGUI: FinalizeDefoldImGui
INFO:DEFOLDIMGUI: imgui_Shutdown
ERROR:RESOURCE: Leaked resources:
ERROR:RESOURCE: Resource: /assets/coins/coin-pro.spinejsonc  ref count: 1

The extension should show a build error in such cases (bundle error in bob as well)

[AGulev]

Old runtime was fine with such animations
We should either show build error or make runtime ignore such issues again

[AGulev]

Validation in Bob has been implemented here: #190.
This issue now relates only to the editor.