### 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)

ERR_FAIL_COND_MSG(p_node == nullptr, "Trying to resolve type of a null node.");
	switch (p_node->type) {
		case GDScriptParser::Node::NONE:
			break; 
		case GDScriptParser::Node::CLASS:
			if (OK == resolve_class_inheritance(static_cast<GDScriptParser::ClassNode *>(p_node), true)) {
				resolve_class_interface(static_cast<GDScriptParser::ClassNode *>(p_node), true);
				resolve_class_body(static_cast<GDScriptParser::ClassNode *>(p_node), true);
			}
			break;
		case GDScriptParser::Node::CONSTANT:
			resolve_constant(static_cast<GDScriptParser::ConstantNode *>(p_node), true);
			break;
		case GDScriptParser::Node::FOR:
			resolve_for(static_cast<GDScriptParser::ForNode *>(p_node));
			break;
		case GDScriptParser::Node::IF:
			resolve_if(static_cast<GDScriptParser::IfNode *>(p_node));
			break;
		case GDScriptParser::Node::SUITE:
			resolve_suite(static_cast<GDScriptParser::SuiteNode *>(p_node));
			break;
		case GDScriptParser::Node::VARIABLE:
			resolve_variable(static_cast<GDScriptParser::VariableNode *>(p_node), true);