YARN-7734. Fix UT failure TestContainerLogsPage#testContainerLogPageAccess. Contributed by Tao Yang.

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/test/java/org/apache/hadoop/yarn/server/nodemanager/webapp/TestContainerLogsPage.java

@@ -259,6 +259,7 @@ public class TestContainerLogsPage {
           new ConcurrentHashMap<ContainerId, Container>();
       when(context.getContainers()).thenReturn(containers);
       when(context.getLocalDirsHandler()).thenReturn(dirsHandler);
+      when(context.getConf()).thenReturn(conf);
 
       MockContainer container = new MockContainer(appAttemptId,
         new AsyncDispatcher(), conf, user, appId, 1);