Update pickAllObjects to use gdja.copyArray

[arthuro555]

Replace the push hack with gdjs.copyArray. Misusing push like this can cause issues when a large amount of objects are used.

(Untested, quick edit made from my phone)

[ClementPasteau]

To get a bit more context, did this cause an issue? If not, what type of issue can this cause?

[arthuro555]

If there are too many objects it can crash the game for exceeding the maximum call stack size, it caused a crash in HelperWesley's game

[4ian]

Better late than never, I think this is perfectly valid :)