### Godot version

4.1.dev

### System information

Win11

### Issue description

I load a non-existing GDScript, but it still returns a valid instance instead of null.
```gdscript
@tool
extends EditorScript

func _run():
	var s = ResourceLoader.load("non_exists.gd", "", ResourceLoader.CACHE_MODE_IGNORE)
	print(s)
	assert(s == null)

```

```
  Attempt to open script 'res://non_exists.gd' resulted in error 'File not found'.
<GDScript#-9223369015982753437>
  res://new_script.gd:7 - Assertion failed.

```

### Steps to reproduce

N/A

### Minimal reproduction project

N/A
pinfo.name = d["name"];
					ERR_CONTINUE(pinfo.name.is_empty());
					if (d.has("hint")) {
						pinfo.hint = PropertyHint(d["hint"].operator int());
					}
					if (d.has("hint_string")) {
						pinfo.hint_string = d["hint_string"];
					}
					if (d.has("usage")) {
						pinfo.usage = d["usage"];
					}
					if (d.has("class_name")) {
						pinfo.class_name = d["class_name"];
					}
					props.push_back(pinfo);
				}
			}
		}
		
		Vector<_GDScriptMemberSort> msort;
		for (const KeyValue<StringName, PropertyInfo> &F : sptr->member_info) {
			_GDScriptMemberSort ms;
			ERR_CONTINUE(!sptr->member_indices.has(F.key));
			ms.index = sptr->member_indices[F.key].index;
			ms.name = F.key;
			msort.push_back(ms);
		}
		msort.sort();
		msort.reverse();
		for (int i = 0; i < msort.size(); i++) {