Normative: Remove support for nested calendar property bags

Previously, "nested" calendar property bags were unwrapped up to one
level. That is, this object:
{
  calendar: {
     // ...Temporal.Calendar methods
  }
}
would not be considered to implement the Calendar protocol, but would have
its calendar property used instead, if it were passed to an API that
required a Calendar protocol object.

These nested property bags are no longer supported. Discussion:
tc39/proposal-temporal#2104 (comment)

See: #2104

UPSTREAM_COMMIT=f431988a6eb4b02c056af820aa7f3c0d0d973d22

lib/ecmascript.ts

@@ -2401,35 +2401,23 @@ export function CalendarInLeapYear(calendar: CalendarSlot, dateLike: CalendarPro
   return result;
 }
 
-export function ToTemporalCalendarSlotValue(calendarLikeParam: string | { calendar: string }): string;
+export function ToTemporalCalendarSlotValue(calendarLike: string | { calendar: string }): string;
 export function ToTemporalCalendarSlotValue(
-  calendarLikeParam: Temporal.CalendarProtocol | { calendar: Temporal.CalendarProtocol }
+  calendarLike: Temporal.CalendarProtocol | { calendar: Temporal.CalendarProtocol }
 ): Temporal.CalendarProtocol;
 export function ToTemporalCalendarSlotValue(
-  calendarLikeParam: string | Temporal.CalendarProtocol | { calendar: string | Temporal.CalendarProtocol }
+  calendarLike: string | Temporal.CalendarProtocol | { calendar: string | Temporal.CalendarProtocol }
 ): string | Temporal.CalendarProtocol;
-export function ToTemporalCalendarSlotValue(calendarLikeParam: CalendarParams['from'][0]) {
-  let calendarLike = calendarLikeParam;
+export function ToTemporalCalendarSlotValue(calendarLike: CalendarParams['from'][0]) {
   if (IsObject(calendarLike)) {
-    if (IsTemporalCalendar(calendarLike)) return calendarLike;
     if (HasSlot(calendarLike, CALENDAR)) return GetSlot(calendarLike, CALENDAR);
     if (IsTemporalTime(calendarLike)) {
       throw new RangeError('Expected a calendar object but received a Temporal.PlainTime');
     }
     if (IsTemporalTimeZone(calendarLike)) {
       throw new RangeError('Expected a calendar object but received a Temporal.TimeZone');
     }
-    if (!('calendar' in calendarLike)) return calendarLike;
-    calendarLike = (calendarLike as { calendar: string | Temporal.CalendarProtocol }).calendar;
-    if (IsObject(calendarLike)) {
-      if (IsTemporalTime(calendarLike)) {
-        throw new RangeError('Expected a calendar object as the calendar property but received a Temporal.PlainTime');
-      }
-      if (IsTemporalTimeZone(calendarLike)) {
-        throw new RangeError('Expected a calendar object as the calendar property but received a Temporal.TimeZone');
-      }
-      if (!('calendar' in calendarLike)) return calendarLike;
-    }
+    return calendarLike;
   }
   const identifier = ToString(calendarLike);
   if (IsBuiltinCalendar(identifier)) return ASCIILowercase(identifier);