Skeleton2D spamming errors after running scene

### Tested versions

- Godot 4.2.1 stable, Godot_v4.3-dev2_win64

### System information

Windows 11, Godot 4.2.1 stable - Forward+ and mobile

### Issue description

I have a Skeleton2D rig working nicely on editor, when i run any scene also works fine, but if close the game or double click other scene and go back to where de skeleton is, an error spam starts.


The only workaround to make this stop for now is open the Skeleton2D Node, delete any of my Modification elements, i can then control+Z and still fine and i didn't lose anything. But if i leave the spam going, it crashes the editor after 2~ min.

### Steps to reproduce

Have a Skeleton2D on scene with modifications in it (in my case 4 2DTwoBoneIK for legs and arms, and 1 2DLookAt, but if i remove all of them and leave one still happening), all bones with rest positions set properly and working fine.

Run the game or change to another scene and go back (doesn't have to be one with skeleton2D)

Close the game.

Check the output tab

### Minimal reproduction project (MRP)

[Skeleton2DMPR.zip](https://github.com/godotengine/godot/files/13978115/Skeleton2DMPR.zip)

Start with the attached Skeleton2DMPR.zip and reproduce the error by running the scene or switching scenes, closing the game, and checking the Output tab. Trace the repeated Skeleton2D modification error and verify that the editor no longer spams errors or crashes after the scene transition.

Written by the indexing model from the issue text.