While joda no longer exists in the apis for 7.x, the compatibility layer
still exists with helper methods mimicking the behavior of joda for
ZonedDateTime objects returned for date fields in scripts. This layer
was originally intended to be removed in 7.0, but is now likely to exist
for the lifetime of 7.x.
This commit adds missing methods from ChronoZonedDateTime to the compat
class. These methods were not part of joda, but are needed to act like a
real ZonedDateTime.
relates #44411