Add PackedVector2iArray and PackedVector3iArray

[acgc99]

Since Vector2i and Vector3i were added, I lack the equivalent packed arrays: PackedVector2iArray and PackedVector3iArray .

I'm using Godot v4.0.beta3.official [01ae26d31] and if I try to set a value of a PackedVector2iArray to a Vector2i I get an error (expected):
Invalid set index '0' (on base: 'PackedVector2Array') with value of type 'Vector2i'

I would really appreciate the addition of these arrays, since I'm working with Vector2i for tiles positions to avoid floating point errors.

[Calinou]

This is already being tracked in #5486.