RigidBody/RigidDynamicBody3D/RigidBody3D apply_impulse does not specify the coordinate space of the impulse

**Your Godot version:**
v4.0.alpha.custom_build [2475393f2]
Also present in 3.x

**Issue description:**
Documentation states that the position is relative to the body in world space, but doesn't specify what space the impulse should be in. Whatever I try doesn't seem to work properly (local vs global), so it would be nice if the docs could clarify.

**URL to the documentation page:**
https://docs.godotengine.org/en/stable/classes/class_rigidbody.html
https://docs.godotengine.org/en/latest/classes/class_rigidbody3d.html?highlight=rigidbody3d#class-rigidbody3d-method-apply-impulse