Fix creating HBase table conflict when multiple kylin instances are starting concurrently

Muliple instances were started at the same time after we installed the kylin. A conflict will occurs because these instances create kylin_metadata_acl table at the same time. The result is that the kylin start failed. The error log is as following:
Caused by: org.apache.hadoop.hbase.TableExistsException: kylin_metadata_acl
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
at org.apache.hadoop.ipc.RemoteException.instantiateException(RemoteException.java:106)
at org.apache.hadoop.ipc.RemoteException.unwrapRemoteException(RemoteException.java:95)
at org.apache.hadoop.hbase.util.ForeignExceptionUtil.toIOException(ForeignExceptionUtil.java:45)
at org.apache.hadoop.hbase.client.HBaseAdmin$ProcedureFuture.convertResult(HBaseAdmin.java:4448)
at org.apache.hadoop.hbase.client.HBaseAdmin$ProcedureFuture.waitProcedureResult(HBaseAdmin.java:4406)
at org.apache.hadoop.hbase.client.HBaseAdmin$ProcedureFuture.get(HBaseAdmin.java:4339)
at org.apache.hadoop.hbase.client.HBaseAdmin.createTable(HBaseAdmin.java:674)
at org.apache.hadoop.hbase.client.HBaseAdmin.createTable(HBaseAdmin.java:604)
at org.apache.kylin.storage.hbase.HBaseConnection.createHTableIfNeeded(HBaseConnection.java:307)
at org.apache.kylin.storage.hbase.HBaseConnection.createHTableIfNeeded(HBaseConnection.java:262)
at org.apache.kylin.rest.security.RealAclHBaseStorage.prepareHBaseTable(RealAclHBaseStorage.java:50)
at org.apache.kylin.rest.security.MockAclHBaseStorage.prepareHBaseTable(MockAclHBaseStorage.java:53)
at org.apache.kylin.rest.service.AclService.init(AclService.java:121)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleElement.invoke(InitDestroyAnnotationBeanPostProcessor.java:344)
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleMetadata.invokeInitMethods(InitDestroyAnnotationBeanPostProcessor.java:295)
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.postProcessBeforeInitialization(InitDestroyAnnotationBeanPostProcessor.java:130)
... 125 more