### 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)

resolve_class_body(p_class);
	if (p_recursive) {
		for (int i = 0; i < p_class->members.size(); i++) {
			GDScriptParser::ClassNode::Member member = p_class->members[i];
			if (member.type == GDScriptParser::ClassNode::Member::CLASS) {
				resolve_class_body(member.m_class, true);
			}
		}
	}
}
void GDScriptAnalyzer::resolve_node(GDScriptParser::Node *p_node, bool p_is_root) {