### Godot version

Godot 4.0 RC 2

### System information

Windows 11

### Issue description

As the title states you get no autocompletion when statically typing.
Of course the code still works, but it shouldn't be neccessary to cast an object to a type it already is.

### Steps to reproduce

1. Create child class with some functionality
![image](https://user-images.githubusercontent.com/100119945/220173809-0b2b2788-d986-4fa7-815c-444268d09c32.png)

2. Get node in parent class and call childs function
![image](https://user-images.githubusercontent.com/100119945/220174167-5ff3c8e9-863e-4fbd-a3cf-d88d34597b39.png)



### Minimal reproduction project

N/A
ScriptLanguage::CodeCompletionOption set("set", ScriptLanguage::CODE_COMPLETION_KIND_PLAIN_TEXT);
			options.insert(set.display, set);
			r_forced = true;
		} break;
		case GDScriptParser::COMPLETION_PROPERTY_METHOD: {
			if (!completion_context.current_class) {
				break;
			}
			for (int i = 0; i < completion_context.current_class->members.size(); i++) {
				const GDScriptParser::ClassNode::Member &member = completion_context.current_class->members[i];
				if (member.type != GDScriptParser::ClassNode::Member::FUNCTION) {
					continue;
				}
				if (member.function->is_static) {
					continue;
				}
				ScriptLanguage::CodeCompletionOption option(member.function->identifier->name, ScriptLanguage::CODE_COMPLETION_KIND_FUNCTION);
				options.insert(option.display, option);
			}
			r_forced = true;
		} break;
		case GDScriptParser::COMPLETION_ASSIGN: {
			GDScriptCompletionIdentifier type;
			if (!completion_context.node || completion_context.node->type != GDScriptParser::Node::ASSIGNMENT) {
				break;
			}
			if (!_guess_expression_type(completion_context, static_cast<const GDScriptParser::AssignmentNode *>(completion_context.node)->assignee, type)) {
				_find_identifiers(completion_context, false, options, 0);
				r_forced = true;
				break;