### 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)

for (int i = 0; i < p_match_branch->patterns.size(); i++) {
		resolve_match_pattern(p_match_branch->patterns[i], p_match_test);
	}
	resolve_suite(p_match_branch->block);
	decide_suite_type(p_match_branch, p_match_branch->block);
}
void GDScriptAnalyzer::resolve_match_pattern(GDScriptParser::PatternNode *p_match_pattern, GDScriptParser::ExpressionNode *p_match_test) {
	if (p_match_pattern == nullptr) {
		return;
	}
	GDScriptParser::DataType result;
	switch (p_match_pattern->pattern_type) {
		case GDScriptParser::PatternNode::PT_LITERAL:
			if (p_match_pattern->literal) {
				reduce_literal(p_match_pattern->literal);
				result = p_match_pattern->literal->get_datatype();
			}
			break;
		case GDScriptParser::PatternNode::PT_EXPRESSION:
			if (p_match_pattern->expression) {
				GDScriptParser::ExpressionNode *expr = p_match_pattern->expression;
				reduce_expression(expr);
				result = expr->get_datatype();
				if (!expr->is_constant) {
					while (expr && expr->type == GDScriptParser::Node::SUBSCRIPT) {
						GDScriptParser::SubscriptNode *sub = static_cast<GDScriptParser::SubscriptNode *>(expr);
						if (!sub->is_attribute) {
							expr = nullptr;
						} else {