### Godot version

4.1.0

### System information

Windows 10, i711800H, Forward+ Vulkan

### Issue description

When using @export_group("Name") in a BaseClass, then inheriting from that BaseClass in another class and there also using @export_group("Name"), with the same group name, then running the project and re-saving the inherited class the project crashes with 
```
ERROR: FATAL: Index p_index = 3 is out of bounds (size() = 3).
   at: get (./core/templates/cowdata.h:155)
```

sometimes the editor crashes too after a while.

### Steps to reproduce

1. open reproduction project
2. Run the project.
3. Open the "super"script
4. Press CTRL + S to save it.

### Minimal reproduction project

[MRP_.zip](https://github.com/godotengine/godot/files/12137412/MRP_.zip)

type = GET_NODE;
		}
	};
	struct IdentifierNode : public ExpressionNode {
		StringName name;
		enum Source {
			UNDEFINED_SOURCE,
			FUNCTION_PARAMETER,
			LOCAL_CONSTANT,
			LOCAL_VARIABLE,
			LOCAL_ITERATOR, 
			LOCAL_BIND, 
			MEMBER_SIGNAL,
			MEMBER_VARIABLE,
			STATIC_VARIABLE,
			MEMBER_CONSTANT,
			INHERITED_VARIABLE,
		};
		Source source = UNDEFINED_SOURCE;
		union {
			ParameterNode *parameter_source = nullptr;
			ConstantNode *constant_source;
			VariableNode *variable_source;
			IdentifierNode *bind_source;
		};
		FunctionNode *source_function = nullptr;
		int usages = 0; 
		IdentifierNode() {