### 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.
case Variant::VECTOR3:
					case Variant::VECTOR4:
					case Variant::QUATERNION:
						result_type.builtin_type = Variant::FLOAT;
						break;
					
					case Variant::PACKED_COLOR_ARRAY:
						result_type.builtin_type = Variant::COLOR;
						break;
					
					case Variant::PACKED_STRING_ARRAY:
					case Variant::STRING:
						result_type.builtin_type = Variant::STRING;
						break;
					
					case Variant::PACKED_VECTOR2_ARRAY:
					case Variant::TRANSFORM2D:
					case Variant::RECT2:
						result_type.builtin_type = Variant::VECTOR2;
						break;
					
					case Variant::RECT2I:
						result_type.builtin_type = Variant::VECTOR2I;
						break;
					
					case Variant::PACKED_VECTOR3_ARRAY:
					case Variant::AABB:
					case Variant::BASIS:
						result_type.builtin_type = Variant::VECTOR3;
						break;