backport: support union query for fields whose data types are datetime and timestamp

[hustjieke]

Is your feature request related to a problem? Please describe.

working issue: #1114

• commit id: 215161d
• commit id: af1508f
• commit id: 3fa2aab

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Additional context

[hustjieke]

related to #1690

[Double0101]

When set up the tmptable, in the function ColumnBinEncoder::EncoderDate::SecondColumn, it only return true when the vc->Type() is DATE. So it only can date union date or timestamp union timestamp;

bool ColumnBinEncoder::EncoderDate::SecondColumn(vcolumn::VirtualColumn *vc) {
  // Possible conversions: only dates.
  if (vc->Type().GetTypeName() != common::ColumnType::DATE) {
    tianmu_control_.lock(vc->ConnInfo()->GetThreadID())
        << "Nontrivial comparison: date with non-date" << system::unlock;
    return false;
  }
...
}

So we can use ATI::IsDateTimeType(type). Then not only type date return true, but alse datetime,timestamp etc return true.