Many tests tested some functionality while asserting that there were no
calls of calendar or time zone methods. We can continue testing the
functionality, but there are no more methods to call, so we can delete
those parts of the tests.
In many cases we created a TimeZone or Calendar instance from a built-in
time zone or calendar. These tests can be trivially adapted to just use
the string ID.
In several tests involving custom calendars, we need to change the
implementation of dateFromFields/monthDayFromFields/yearMonthFromFields so
that the returned object gets the receiver as its calendar after chaining
up to the builtin implementation.
Normative PR: https://github.com/tc39/proposal-temporal/pull/2482
