Currently the test picks random java.util.TimeZone ids in some places.
Internally we still need to convert back to joda DateTimeZone by id
occassionally (e.g. when serializing to pre 6.3 versions). There are
some deprecated "SystemV/*" time zones that Jodas DateTimeZone refuses
to convert. This change excludes those rare cases from the set of
allowed random time zones. It would be quiet odd for them to appear in
practice.
Closes#30156
d0416c76fe