Joint destroy error when using remove_child.

[Gyrth]

Godot version:
3.0.6

OS/device including version:
Windows 10

Issue description:
Error message about joint destroying when only removing_child.

0:00:00:0741 - A body with a joints is destroyed. Please check the implementation in order to destroy the joint before the body.
----------
Type:Warning
Description: 
Time: 0:00:00:0741
C Error: A body with a joints is destroyed. Please check the implementation in order to destroy the joint before the body.
C Source: modules/bullet/rigid_body_bullet.cpp:411
C Function: assert_no_constraints

Steps to reproduce:

• Create scene with a HingJoint in it.
• Create level scene which has that HingeJoint scene instanced.
• remove_child the HingeJoint scene on_ready.

Minimal reproduction project:
joint_issue.zip

[LinuxUserGD]

What happens if you remove_child the joint first?

[LinuxUserGD]

With a "joints"?

[Gyrth]

I don't want to destroy anything, just remove the child from the scenetree.

[PLyczkowski]

Yup, same here. Reparenting stuff with joints breaks them and throws this error...

[KoBeWi]

Still valid in 2ba96f0

[pouleyKetchoupp]

Fixed by #44703, closing.