LibJS: Update spec comments to use ToZeroPaddedDecimalString AO

This is an editorial change in the ECMA-262 and Temporal specs.

See:
- 843d8b8
- f9211d9

Note that we don't actually need to implement the AO as we already have
String::formatted() for this, and use unified format strings instead of
zero-padding in individual steps in many cases anyway.

Userland/Libraries/LibJS/Runtime/Temporal/PlainMonthDay.cpp

@@ -176,8 +176,8 @@ ThrowCompletionOr<String> temporal_month_day_to_string(GlobalObject& global_obje
     // 1. Assert: Type(monthDay) is Object.
     // 2. Assert: monthDay has an [[InitializedTemporalMonthDay]] internal slot.
 
-    // 3. Let month be monthDay.[[ISOMonth]] formatted as a two-digit decimal number, padded to the left with a zero if necessary.
-    // 4. Let day be monthDay.[[ISODay]] formatted as a two-digit decimal number, padded to the left with a zero if necessary.
+    // 3. Let month be ToZeroPaddedDecimalString(temporalDate.[[ISOMonth]], 2).
+    // 4. Let day be ToZeroPaddedDecimalString(temporalDate.[[ISODay]], 2).
     // 5. Let result be the string-concatenation of month, the code unit 0x002D (HYPHEN-MINUS), and day.
     auto result = String::formatted("{:02}-{:02}", month_day.iso_month(), month_day.iso_day());