YARN-4248. Followup patch adding asf-licence exclusions for json test files

(cherry picked from commit 9f50e13d5dc329c3a6df7f9bcaf2f29b35adc52b)

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/pom.xml

@@ -321,6 +321,17 @@
           </execution>
         </executions>
       </plugin>
+      <plugin>
+        <groupId>org.apache.rat</groupId>
+        <artifactId>apache-rat-plugin</artifactId>
+        <configuration>
+          <excludes>
+            <exclude>src/test/resources/submit-reservation.json</exclude>
+            <exclude>src/test/resources/delete-reservation.json</exclude>
+            <exclude>src/test/resources/update-reservation.json</exclude>
+          </excludes>
+        </configuration>
+      </plugin>
     </plugins>
   </build>