fix an incorrect call in ClientSideIteratorScanner (#6036)

`batchTimeout` was set to `scanner.getTimeout(MILLISECONDS)` instead of `scanner.getBatchTimeout(MILLISECONDS)`

Author: kevinrr888

core/src/main/java/org/apache/accumulo/core/client/ClientSideIteratorScanner.java

@@ -177,7 +177,7 @@ public ClientSideIteratorScanner(final Scanner scanner) {
     this.range = scanner.getRange();
     this.size = scanner.getBatchSize();
     this.retryTimeout = scanner.getTimeout(MILLISECONDS);
-    this.batchTimeout = scanner.getTimeout(MILLISECONDS);
+    this.batchTimeout = scanner.getBatchTimeout(MILLISECONDS);
     this.readaheadThreshold = scanner.getReadaheadThreshold();
     SamplerConfiguration samplerConfig = scanner.getSamplerConfiguration();
     if (samplerConfig != null) {