Fix NPE when streaming query is started but not yet executed.

Co-authored-by: Szabolcs Vasas <svasas@groupon.com>

Author: szvasas

src/main/scala/net/heartsavior/spark/KafkaOffsetCommitterListener.scala

@@ -38,8 +38,8 @@ class KafkaOffsetCommitterListener extends StreamingQueryListener with Logging {
     val query = SparkSession.active.streams.get(event.progress.id)
     if (query != null) {
       val exec = query match {
-        case query: StreamingQueryWrapper => Some(query.streamingQuery.lastExecution)
-        case query: StreamExecution => Some(query.lastExecution)
+        case query: StreamingQueryWrapper => Option(query.streamingQuery.lastExecution)
+        case query: StreamExecution => Option(query.lastExecution)
         case _ =>
           logWarning(s"Unexpected type of streaming query: ${query.getClass}")
           None