[ASTERIXDB-3144][HYR][RT] Make sampling job support multiple partitions

- user model changes: no
- storage format changes: no
- interface changes: no

Details:
This patch changes the sampling job to support
operating on multiple partitions. This is a step towards
achieving compute/storage separation.

Change-Id: If9abc68402adfe47ddeb5f1b1499e3414369f506
Reviewed-on: https://asterix-gerrit.ics.uci.edu/c/asterixdb/+/17511
Reviewed-by: Ali Alsuliman <ali.al.solaiman@gmail.com>
Reviewed-by: Murtadha Hubail <mhubail@apache.org>
Integration-Tests: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Tested-by: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
diff --git a/hyracks-fullstack/hyracks/hyracks-storage-am-btree/pom.xml b/hyracks-fullstack/hyracks/hyracks-storage-am-btree/pom.xml
index 8a08074..573656f 100644
--- a/hyracks-fullstack/hyracks/hyracks-storage-am-btree/pom.xml
+++ b/hyracks-fullstack/hyracks/hyracks-storage-am-btree/pom.xml
@@ -117,5 +117,12 @@
       <artifactId>hyracks-util</artifactId>
       <version>${project.version}</version>
     </dependency>
+    <dependency>
+      <groupId>org.apache.hyracks</groupId>
+      <artifactId>hyracks-util</artifactId>
+      <version>${project.version}</version>
+      <type>test-jar</type>
+      <scope>test</scope>
+    </dependency>
   </dependencies>
 </project>
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