Presto queries on Pinot segments failing with NPE

Presto query on PInot segment path failing with the following error. The data table returned by the server is null. Most probably a fix in presto-pinot driver https://github.com/prestodb/presto-pinot-driver

```
java.lang.NullPointerException: null value in entry: Server_streampinot-stg22-phx3_7090=null
at com.google.common.collect.CollectPreconditions.checkEntryNotNull(CollectPreconditions.java:32)
at com.google.common.collect.SingletonImmutableBiMap.(SingletonImmutableBiMap.java:42)
at com.google.common.collect.ImmutableBiMap.of(ImmutableBiMap.java:72)
at com.google.common.collect.ImmutableMap.of(ImmutableMap.java:124)
at com.google.common.collect.ImmutableMap.copyOf(ImmutableMap.java:458)
at com.google.common.collect.ImmutableMap.copyOf(ImmutableMap.java:437)
at com.facebook.presto.pinot.PinotSegmentPageSource.queryPinot(PinotSegmentPageSource.java:242)
at com.facebook.presto.pinot.PinotSegmentPageSource.fetchPinotData(PinotSegmentPageSource.java:214)
at com.facebook.presto.pinot.PinotSegmentPageSource.getNextPage(PinotSegmentPageSource.java:161)
at com.facebook.presto.operator.ScanFilterAndProjectOperator.processPageSource(ScanFilterAndProjectOperator.java:276)
at com.facebook.presto.operator.ScanFilterAndProjectOperator.getOutput(ScanFilterAndProjectOperator.java:241)
at com.facebook.presto.operator.Driver.processInternal(Driver.java:418)
```