EditorPlugin.remove_inspector_plugin() doesn't clean references, creating leaked instances at exit

[AnidemDex]

Godot version

v3.4.stable.official [206ba70]

System information

Windows 11 x64

Issue description

I was working in a integration of two different plugins, each one has different uses.

Making some experiments I discovered that, if you try to add more than 1 editor inspector plugin, at the moment you try to remove them, they'll not be removed from internal data of the inspector, causing leaked instances on exit.

ERROR: Condition "_first != nullptr" is true.
   at: ~List (./core/self_list.h:108)
ERROR: Condition "_first != nullptr" is true.
   at: ~List (./core/self_list.h:108)
WARNING: ObjectDB instances leaked at exit (run with --verbose for details).
     at: cleanup (core/object.cpp:2064)
Leaked instance: GDScript:27266 - Resource path:
Leaked instance: GDScriptNativeClass:1107
Leaked instance: EditorInspectorPlugin:29377
Hint: Leaked instances typically happen when nodes are removed from the scene tree (with `remove_child()`) but not freed (with `free()` or `queue_free()`).
Orphan StringName: GDScriptNativeClass
Orphan StringName: EditorInspectorPlugin
Orphan StringName: _init
Orphan StringName: res://addons/textalog/plugin_script.gd
Orphan StringName: GDScript
StringName: 5 unclaimed string names at exit.

Relevant code on source:

godot/editor/editor_inspector.cpp

Line 2182 in 96e70ac

void EditorInspector::remove_inspector_plugin(const Ref<EditorInspectorPlugin> &p_plugin) {

Steps to reproduce

Create a new plugin and use this code:

tool
extends EditorPlugin

class a extends EditorInspectorPlugin:
	pass

class b extends EditorInspectorPlugin:
	pass

var inspector_a = a.new()
var inspector_b = b.new()

func _enter_tree():
	add_inspector_plugin(inspector_a)
	add_inspector_plugin(inspector_b)

func _exit_tree():
	remove_inspector_plugin(inspector_a)
	remove_inspector_plugin(inspector_b)

The first inspector (inspector_a) will be removed without problems, but inspector_b will cause leaked instances when you close the editor.

Minimal reproduction project

No response