Fallback TimeZoneAwareExpression that only support UTC with zoneId instead of timeZone config

[thirtiseven]

In some TimeZoneAwareExpression that plugin supports only UTC, the expression will fallback according to GpuOverrides.isUTCTimezone. In some case like when we call an expression directly by passing a timezone as it's parameter, like in Spark UT:

checkEvaluation(
      StructsToJson(Map.empty, struct, Option(PST.getId)),
      """{"t":"2015-12-31T16:00:00.000-08:00"}"""
    )

The fallback doesn't work because it didn't change any configuration.

For expressions that support timezone, we will check the expr.zoneId in BaseExprMeta.getZoneId(), I hope we can use it instead of reading config when checking UTC timezone too.