### 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.
} else {
				type.type_source = GDScriptParser::DataType::INFERRED;
			}
		} else if (!specified_type.is_variant()) {
			if (initializer_type.is_variant() || !initializer_type.is_hard_type()) {
				mark_node_unsafe(p_assignable->initializer);
				p_assignable->use_conversion_assign = true;
				if (!initializer_type.is_variant() && !is_type_compatible(specified_type, initializer_type, true, p_assignable->initializer)) {
					downgrade_node_type_source(p_assignable->initializer);
				}
			} else if (!is_type_compatible(specified_type, initializer_type, true, p_assignable->initializer)) {
				if (!is_constant && is_type_compatible(initializer_type, specified_type)) {
					mark_node_unsafe(p_assignable->initializer);
					p_assignable->use_conversion_assign = true;
				} else {
					push_error(vformat(R"(Cannot assign a value of type %s to %s "%s" with specified type %s.)", initializer_type.to_string(), p_kind, p_assignable->identifier->name, specified_type.to_string()), p_assignable->initializer);
				}
			} else if (specified_type.has_container_element_type() && !initializer_type.has_container_element_type()) {
				mark_node_unsafe(p_assignable->initializer);
#ifdef DEBUG_ENABLED
			} else if (specified_type.builtin_type == Variant::INT && initializer_type.builtin_type == Variant::FLOAT) {
				parser->push_warning(p_assignable->initializer, GDScriptWarning::NARROWING_CONVERSION);
#endif
			}
		}
	}
	type.is_constant = is_constant;
	p_assignable->set_datatype(type);
}
void GDScriptAnalyzer::resolve_variable(GDScriptParser::VariableNode *p_variable, bool p_is_local) {