### 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)

if (p_a.kind == GDScriptParser::DataType::ENUM) {
		if (p_a.is_meta_type) {
			a_type = Variant::DICTIONARY;
		} else {
			a_type = Variant::INT;
		}
	}
	if (p_b.kind == GDScriptParser::DataType::ENUM) {
		if (p_b.is_meta_type) {
			b_type = Variant::DICTIONARY;
		} else {
			b_type = Variant::INT;
		}
	}
	Variant::ValidatedOperatorEvaluator op_eval = Variant::get_validated_operator_evaluator(p_operation, a_type, b_type);
	bool hard_operation = p_a.is_hard_type() && p_b.is_hard_type();
	bool validated = op_eval != nullptr;
	GDScriptParser::DataType result;
	if (validated) {
		r_valid = true;
		result.type_source = hard_operation ? GDScriptParser::DataType::ANNOTATED_INFERRED : GDScriptParser::DataType::INFERRED;
		result.kind = GDScriptParser::DataType::BUILTIN;
		result.builtin_type = Variant::get_operator_return_type(p_operation, a_type, b_type);
	} else {
		r_valid = !hard_operation;
		result.kind = GDScriptParser::DataType::VARIANT;
	}
	return result;
}
bool GDScriptAnalyzer::is_type_compatible(const GDScriptParser::DataType &p_target, const GDScriptParser::DataType &p_source, bool p_allow_implicit_conversion, const GDScriptParser::Node *p_source_node) {