### 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)

expr = sub->base;
						}
					}
					if (!expr || expr->type != GDScriptParser::Node::IDENTIFIER) {
						push_error(R"(Expression in match pattern must be a constant expression, an identifier, or an attribute access ("A.B").)", expr);
					}
				}
			}
			break;
		case GDScriptParser::PatternNode::PT_BIND:
			if (p_match_test != nullptr) {
				result = p_match_test->get_datatype();
			} else {
				result.kind = GDScriptParser::DataType::VARIANT;
			}
			p_match_pattern->bind->set_datatype(result);
#ifdef DEBUG_ENABLED
			is_shadowing(p_match_pattern->bind, "pattern bind");
			if (p_match_pattern->bind->usages == 0 && !String(p_match_pattern->bind->name).begins_with("_")) {
				parser->push_warning(p_match_pattern->bind, GDScriptWarning::UNUSED_VARIABLE, p_match_pattern->bind->name);
			}
#endif
			break;
		case GDScriptParser::PatternNode::PT_ARRAY:
			for (int i = 0; i < p_match_pattern->array.size(); i++) {
				resolve_match_pattern(p_match_pattern->array[i], nullptr);
				decide_suite_type(p_match_pattern, p_match_pattern->array[i]);
			}
			result = p_match_pattern->get_datatype();
			break;