Update presto-base-arrow-flight/src/main/java/com/facebook/plugin/arr…

…ow/ArrowFlightClientHandler.java

Co-authored-by: Timothy Meehan <tim@timdmeehan.com>

presto-base-arrow-flight/src/main/java/com/facebook/plugin/arrow/ArrowFlightClientHandler.java

@@ -38,7 +38,7 @@ public abstract class ArrowFlightClientHandler
 
     public ArrowFlightClientHandler(ArrowFlightConfig config)
     {
-        this.config = config;
+        this.config = requireNonNull(config, "config is null");
     }
 
     private ArrowFlightClient initializeClient(Optional<String> uri)