Unable to use negative indices in Array.remove

[abelgutierrez99]

Godot version: 3.2.3

OS/device including version: Windows 10 x 64

Issue description:
When you create an Array and later use Array.remove(index), index must be positive, althouth Arrays can be indexed using negative indices. The debugger message in the minimal reproduction project is: E 0:00:00.895 remove: Index p_index = -1 is out of bounds (size() = 3). <C++ Source> ./core/cowdata.h:161 @ remove() Spatial.gd:7 @ _ready()

Maybe other methods have the same problem.

Steps to reproduce:
Create an Array and try to remove one element using a negative index with Array.remove

Minimal reproduction project:

Github.zip

[Calinou]

This needs to be implemented. See also #37209.