Follow-up to Intl.DurationFormat #3912

[ptomato]

Address comments from #3912.

• test/intl402/DurationFormat/constructor-option-read-order.js: localeMatcher is read before numberingSystem but isn't in resolvedOptions(). Probably better to use a Proxy that pushes all Get operations to the array, rather than just the ones in resolvedOptions().
• test/intl402/DurationFormat/prototype/resolvedOptions/return-keys-order-default.js: fractionalSeconds is added last if not undefined. Consider testing the order again when constructing the object with e.g. new Intl.DurationFormat('en', { fractionalDigits: 0 }).

cc @FrankYFTang