### 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)

reduce_dictionary(static_cast<GDScriptParser::DictionaryNode *>(p_expression));
			break;
		case GDScriptParser::Node::GET_NODE:
			reduce_get_node(static_cast<GDScriptParser::GetNodeNode *>(p_expression));
			break;
		case GDScriptParser::Node::IDENTIFIER:
			reduce_identifier(static_cast<GDScriptParser::IdentifierNode *>(p_expression));
			break;
		case GDScriptParser::Node::LAMBDA:
			reduce_lambda(static_cast<GDScriptParser::LambdaNode *>(p_expression));
			break;
		case GDScriptParser::Node::LITERAL:
			reduce_literal(static_cast<GDScriptParser::LiteralNode *>(p_expression));
			break;
		case GDScriptParser::Node::PRELOAD:
			reduce_preload(static_cast<GDScriptParser::PreloadNode *>(p_expression));
			break;
		case GDScriptParser::Node::SELF:
			reduce_self(static_cast<GDScriptParser::SelfNode *>(p_expression));
			break;
		case GDScriptParser::Node::SUBSCRIPT:
			reduce_subscript(static_cast<GDScriptParser::SubscriptNode *>(p_expression));
			break;
		case GDScriptParser::Node::TERNARY_OPERATOR:
			reduce_ternary_op(static_cast<GDScriptParser::TernaryOpNode *>(p_expression), p_is_root);
			break;
		case GDScriptParser::Node::TYPE_TEST:
			reduce_type_test(static_cast<GDScriptParser::TypeTestNode *>(p_expression));
			break;
		case GDScriptParser::Node::UNARY_OPERATOR: