fix toctree in multi_cluster/index_en.rst

doc/v2/howto/cluster/multi_cluster/index_en.rst

@@ -8,28 +8,28 @@ The user's cluster environment is not the same. To facilitate everyone's deploym
 ..  toctree::
   :maxdepth: 1
 
-  k8s_cn.md
-  k8s_distributed_cn.md
+  k8s_en.md
+  k8s_distributed_en.md
 
 `OpenMPI <https://www.open-mpi.org>`_ is a mature high-performance parallel computing framework, which is widely used in the field of HPC. The following guide describes how to use OpenMPI to build PaddlePaddle's cluster training task:
 
 ..  toctree::
   :maxdepth: 1
 
-  openmpi_cn.md
+  openmpi_en.md
 
 `Fabric <http://www.fabfile.org>`_ is a convenient tool for program deployment and management. We provide a way to deploy and manage with Fabric. If you want to know more about it, please read the following guidelines:
 
 ..  toctree::
   :maxdepth: 1
 
-  fabric_cn.md
+  fabric_en.md
 
 We also support the deployment of PaddlePaddle on AWS. Learn more about:
 
 ..  toctree::
   :maxdepth: 1
 
-  k8s_aws_cn.md
+  k8s_aws_en.md
 
-The examples can be found under `cluster_train_v2 <https://github.com/PaddlePaddle/Paddle/tree/develop/paddle/scripts/cluster_train_v2>`_ .
\ No newline at end of file
+The examples can be found under `cluster_train_v2 <https://github.com/PaddlePaddle/Paddle/tree/develop/paddle/scripts/cluster_train_v2>`_ .