YARN-8899. Fixed minicluster dependency on yarn-server-web-proxy.

            Contributed by Robert Kanter

hadoop-minicluster/pom.xml

@@ -104,6 +104,12 @@
       <artifactId>hadoop-mapreduce-client-hs</artifactId>
       <scope>compile</scope>
     </dependency>
+
+    <dependency>
+      <groupId>org.apache.hadoop</groupId>
+      <artifactId>hadoop-yarn-server-web-proxy</artifactId>
+      <scope>compile</scope>
+    </dependency>
   </dependencies>
 
 </project>