### 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)

Variant value;
	if (p_expression == nullptr) {
		return value;
	}
	if (p_expression->is_constant) {
		is_reduced = true;
		value = p_expression->reduced_value;
	} else if (p_expression->type == GDScriptParser::Node::ARRAY) {
		value = make_array_reduced_value(static_cast<GDScriptParser::ArrayNode *>(p_expression), is_reduced);
	} else if (p_expression->type == GDScriptParser::Node::DICTIONARY) {
		value = make_dictionary_reduced_value(static_cast<GDScriptParser::DictionaryNode *>(p_expression), is_reduced);
	} else if (p_expression->type == GDScriptParser::Node::SUBSCRIPT) {
		value = make_subscript_reduced_value(static_cast<GDScriptParser::SubscriptNode *>(p_expression), is_reduced);
	}
	return value;
}
Variant GDScriptAnalyzer::make_array_reduced_value(GDScriptParser::ArrayNode *p_array, bool &is_reduced) {