### 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_unary_op(static_cast<GDScriptParser::UnaryOpNode *>(p_expression));
			break;
		
		case GDScriptParser::Node::NONE:
		case GDScriptParser::Node::ANNOTATION:
		case GDScriptParser::Node::ASSERT:
		case GDScriptParser::Node::BREAK:
		case GDScriptParser::Node::BREAKPOINT:
		case GDScriptParser::Node::CLASS:
		case GDScriptParser::Node::CONSTANT:
		case GDScriptParser::Node::CONTINUE:
		case GDScriptParser::Node::ENUM:
		case GDScriptParser::Node::FOR:
		case GDScriptParser::Node::FUNCTION:
		case GDScriptParser::Node::IF:
		case GDScriptParser::Node::MATCH:
		case GDScriptParser::Node::MATCH_BRANCH:
		case GDScriptParser::Node::PARAMETER:
		case GDScriptParser::Node::PASS:
		case GDScriptParser::Node::PATTERN:
		case GDScriptParser::Node::RETURN:
		case GDScriptParser::Node::SIGNAL:
		case GDScriptParser::Node::SUITE:
		case GDScriptParser::Node::TYPE:
		case GDScriptParser::Node::VARIABLE:
		case GDScriptParser::Node::WHILE:
			ERR_FAIL_MSG("Reaching unreachable case");
	}
}
void GDScriptAnalyzer::reduce_array(GDScriptParser::ArrayNode *p_array) {