Fix: Resource encoding to dict

[mashumafi]

Addressing #64202. Unless there is some technical reason to keep this logic of forcing only resource files being encoded then maybe this check can be removed.

The error before said: Invalid type in GDScript utility function '<unknown function>'. Cannot convert argument 1 from Object to Dictionary

Bugsquad edit:

• Fixes Call inst2dict on class Example extends Resource returned by Resource::duplicate() will throw GDScript utility function error #64202

[dalexeev]

Unless there is some technical reason to keep this logic of forcing only resource files being encoded then maybe this check can be removed.

The path is needed in order to restore the value in dict_to_inst() later:

godot/modules/gdscript/gdscript_utility_functions.cpp

Lines 323 to 329 in 92ffad9

	Ref<Script> scr = ResourceLoader::load(d["@path"]);
	if (!scr.is_valid()) {
	r_error.error = Callable::CallError::CALL_ERROR_INVALID_ARGUMENT;
	r_error.argument = 0;
	r_error.expected = Variant::OBJECT;
	*r_ret = RTR("Invalid instance dictionary format (can't load script at @path)");
	return;

I think we should make the error message clearer instead.

var_to_str() has exactly the same limitation (and var_to_bytes() should too, see #78219).

[mashumafi]

Might not be a bug