### Godot version

v4.0.rc1.official [8843d9ad3]

### System information

Lubuntu

### Issue description

You can't use + or += to mutate typed arrays.

It seems to be not correctly getting the type information from the second operand.

An erudite poster on the discord puts it differently:
> it's more like operator + doesn't retain Array typing
> the syntax for Array Concatenation via operators, but the idea gets across i think


The error you see is:
```Trying to assign an array of type "Array" to a variable of type "Array[int]".```


### Steps to reproduce

```
	var Alice: Array[int] = [1,2,3]
	var Bob: Array[int] = [4,5,6]
	Alice += Bob
```
This will crash with the above error message.

### Minimal reproduction project

[plus_syntax_broken_demo_project.zip](https://github.com/godotengine/godot/files/10694514/plus_syntax_broken_demo_project.zip)

break;
			case GDScriptParser::ClassNode::Member::GROUP:
				
				break;
			case GDScriptParser::ClassNode::Member::UNDEFINED:
				ERR_PRINT("Trying to resolve undefined member.");
				break;
		}
#ifdef DEBUG_ENABLED
		parser->ignored_warnings = previously_ignored_warnings;
#endif
	}
	parser->current_class = previous_class;
}
void GDScriptAnalyzer::resolve_class_interface(GDScriptParser::ClassNode *p_class, const GDScriptParser::Node *p_source) {
	if (p_source == nullptr && parser->has_class(p_class)) {
		p_source = p_class;
	}
#ifdef DEBUG_ENABLED
	bool has_static_data = p_class->has_static_data;
#endif
	if (!p_class->resolved_interface) {
		if (!parser->has_class(p_class)) {
			String script_path = p_class->get_datatype().script_path;
			Ref<GDScriptParserRef> parser_ref = get_parser_for(script_path);
			if (parser_ref.is_null()) {
				push_error(vformat(R"(Could not find script "%s".)", script_path), p_source);
				return;
			}
			Error err = parser_ref->raise_status(GDScriptParserRef::PARSED);