AMBARI-20902.Ambari build failure after npm to yarn package manager migration.(Venkata Sairam)

pom.xml

@@ -398,6 +398,7 @@
             <exclude>ambari-metrics/**/.*/**</exclude>
             <!-- generated DDL-->
             <exclude>**/createDDL.jdbc</exclude>
+            <exclude>**/yarn.lock</exclude>
           </excludes>
         </configuration>
         <executions>