Temporal: Missing coverage for "reject" overflow handling in NonISODateAdd

This case seems uncovered, because it's not correctly implemented in SpiderMonkey, but I don't see any related failures when running all test262 Temporal tests:
```js
// Actual: No RangeError in SpiderMonkey
// Expected: Throws a RangeError
Temporal.PlainDate.from({calendar: "hebrew", year: 5000, month: 6, day: 1}).add("P1Y1M", {overflow: "reject"})
```
