### 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)

break;
					case Callable::CallError::CALL_ERROR_TOO_FEW_ARGUMENTS:
						push_error(vformat(R"(Too few arguments for %s constructor. Received %d but expected %d.)", Variant::get_type_name(builtin_type), p_call->arguments.size(), err.expected), p_call);
						break;
					case Callable::CallError::CALL_ERROR_INSTANCE_IS_NULL:
					case Callable::CallError::CALL_ERROR_METHOD_NOT_CONST:
						break; 
					case Callable::CallError::CALL_OK:
						p_call->is_constant = true;
						p_call->reduced_value = value;
						break;
				}
			} else {
				
				
				if (p_call->arguments.size() == 1) {
					GDScriptParser::DataType arg_type = p_call->arguments[0]->get_datatype();
					if (arg_type.is_variant()) {
						mark_node_unsafe(p_call->arguments[0]);
					} else {
						if (arg_type.kind == GDScriptParser::DataType::BUILTIN && arg_type.builtin_type == builtin_type) {
							
							p_call->set_datatype(call_type);
							return;
						}
					}
				}
				List<MethodInfo> constructors;
				Variant::get_constructor_list(builtin_type, &constructors);
				bool match = false;