Polyfill: Replace unreachable overshoot block with assertion in calendarToIsoDate#3292

ptomato merged 3 commits intotc39:maintc39/proposal-temporal:mainfrom

jessealama:calendarToIsoDate-overshoot-dead-codejessealama/proposal-temporal:calendarToIsoDate-overshoot-dead-codeCopy head branch name to clipboard