### Godot version

4.0.beta10

### System information

Windows 11

### Issue description
UPDATE: This problem only occurs when the source code contains inner classes

Before 4.0.Beta9, I could get a GDScript instance by `GDScript.new()` and then set the `source_code` property and then `reload()`, but now it throws an error 
```
USER SCRIPT ERROR: Parse Error: Could not find script "".
   at: GDScript::reload (built-in:1644)
```
In my software, I use the above method when the user modifies the code text, and then read the godot log to implement real-time error checking of the custom user script editor. But now this functionality is completely broken

### Steps to reproduce

1. Create a GDScript instance by `GDScript.new()`
2. set the `source_code` property and then `reload()`

### Minimal reproduction project

N/A
GDScript *sptr = script.ptr();
	if (unlikely(p_method == SNAME("_ready"))) {
		
		while (sptr) {
			if (sptr->implicit_ready) {
				sptr->implicit_ready->call(this, nullptr, 0, r_error);
			}
			sptr = sptr->_base;
		}
		
		sptr = script.ptr();
	}
	while (sptr) {
		HashMap<StringName, GDScriptFunction *>::Iterator E = sptr->member_functions.find(p_method);
		if (E) {
			return E->value->call(this, p_args, p_argcount, r_error);
		}
		sptr = sptr->_base;
	}
	r_error.error = Callable::CallError::CALL_ERROR_INVALID_METHOD;
	return Variant();
}
void GDScriptInstance::notification(int p_notification) {