### Godot version

Beta 17, master

### System information

Windows 11

### Issue description

Godot gets a hard crash while attempting to code-complete for member `const` of a class.

### Steps to reproduce

```GDScript
enum E { V1 }

const e := E
```

And then type a `.` after the last `E`, which triggers code hints/auto-completion for subscripts based on `E` and causes a hard crash.

Does not happen for `var e := E.V1`.

### Minimal reproduction project

See above.
}
				push_error(vformat(R"(Cannot find constant "%s" on base "%s".%s)", name, base.to_string(), rename_hint), p_identifier);
#else 
				push_error(vformat(R"(Cannot find constant "%s" on base "%s".)", name, base.to_string()), p_identifier);
#endif 
#else
				push_error(vformat(R"(Cannot find constant "%s" on base "%s".)", name, base.to_string()), p_identifier);
#endif
			}
		} else {
			switch (base.builtin_type) {
				case Variant::NIL: {
					if (base.is_hard_type()) {
						push_error(vformat(R"(Invalid get index "%s" on base Nil)", name), p_identifier);
					}
					return;
				}
				case Variant::DICTIONARY: {
					GDScriptParser::DataType dummy;
					dummy.kind = GDScriptParser::DataType::VARIANT;
					p_identifier->set_datatype(dummy);
					return;
				}
				default: {
					Callable::CallError temp;
					Variant dummy;
					Variant::construct(base.builtin_type, dummy, nullptr, 0, temp);
					List<PropertyInfo> properties;
					dummy.get_property_list(&properties);
					for (const PropertyInfo &prop : properties) {