Repository: godot
Issue: ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
Labels: bug,topic:rendering,needs testing,topic:3d

### Godot version

v3.4.3.stable.official [242c05d12]

### System information

Mac OSX (Intel 2019)

### Issue description

Sometimes when un-mounting a Sprite3D, my logs will get spammed with Gigabytes of the same error.

Error can be found in the details below:

<details>
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
   at: _disconnect (core/object.cpp:1538) - Condition "!s->slot_map.has(target)" is true.
ERROR: Disconnecting nonexistent signal 'changed', slot: 4300:_texture_changed.
</details>

I see there is no signal `changed` in `Sprite3D`, but there is in `Sprite2D`.  Perhaps this is missing?

<img width="743" alt="Screenshot 2022-03-03 at 19 35 56" src="https://user-images.githubusercontent.com/100964/156609185-a9e0f7b8-590a-4b3e-a6cd-debe411b1278.png">



### Steps to reproduce

Unmount a Sprite3D and then try to change the texture? I'm not really sure how to reproduce this one 🤔 

### Minimal reproduction project

_No response_