YARN-8898. Fix CheckStyle.

Author: slfan1989

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-common/src/main/java/org/apache/hadoop/yarn/server/federation/store/impl/MemoryFederationStateStore.java

@@ -34,10 +34,14 @@
 import org.apache.hadoop.classification.VisibleForTesting;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.security.token.delegation.DelegationKey;
-import org.apache.hadoop.yarn.api.records.*;
+import org.apache.hadoop.yarn.api.records.ApplicationSubmissionContext;
 import org.apache.hadoop.yarn.exceptions.YarnRuntimeException;
 import org.apache.hadoop.yarn.proto.YarnServerCommonProtos.VersionProto;
 import org.apache.hadoop.yarn.security.client.RMDelegationTokenIdentifier;
+import org.apache.hadoop.yarn.api.records.ApplicationId;
+import org.apache.hadoop.yarn.api.records.ReservationId;
+import org.apache.hadoop.yarn.api.records.Priority;
+import org.apache.hadoop.yarn.api.records.Resource;
 import org.apache.hadoop.yarn.conf.YarnConfiguration;
 import org.apache.hadoop.yarn.exceptions.YarnException;
 import org.apache.hadoop.yarn.server.federation.store.FederationStateStore;