[V0.4 Release] Kubeflow training service: Remove unued kubernetesServer config entry (#444)

* Remove unused kubernetesServer config entry in config file and schema validation

docs/KubeflowMode.md

@@ -67,7 +67,6 @@ kubeflowConfig:
   nfs:
     server: {your_nfs_server}
     path: {your_nfs_server_exported_path}
-  kubernetesServer: {your_kubernetes_api_server_ip}
 ```
 If you use Azure Kubernets Service, you should  set `kubeflowConfig` in your config yaml file as follows:
 ```

examples/trials/mnist-distributed/config_kubeflow.yml

@@ -42,4 +42,3 @@ kubeflowConfig:
     server: {your_nfs_server_ip}
     # Your NFS server export path, like /var/nfs/nni
     path: {your_nfs_server_export_path}
-  kubernetesServer: 10.10.10.10

src/nni_manager/rest_server/restValidationSchemas.ts

@@ -72,7 +72,6 @@ export namespace ValidationSchemas {
                     server: joi.string().min(1).required(),
                     path: joi.string().min(1).required()
                 }),
-                kubernetesServer: joi.string().min(1),
                 keyVault: joi.object({
                     vaultName: joi.string().regex(/^([0-9]|[a-z]|[A-Z]|-){1,127}$/),
                     name: joi.string().regex(/^([0-9]|[a-z]|[A-Z]|-){1,127}$/)

src/nni_manager/training_service/kubeflow/kubeflowConfig.ts

@@ -46,7 +46,6 @@ export class KubeflowClusterConfig {
     /** Name of Kubeflow operator, like tf-operator */
     public readonly operator: KubeflowOperator;
     public readonly nfs?: NFSConfig;
-    public readonly kubernetesServer: string;
     public readonly keyVault?: keyVaultConfig;
     public readonly azureStorage?: AzureStorage;
     
@@ -56,10 +55,9 @@ export class KubeflowClusterConfig {
      * @param passWord password of Kubeflow Cluster
      * @param host Host IP of Kubeflow Cluster
      */
-    constructor(operator: KubeflowOperator, kubernetesServer : string, nfs?: NFSConfig, keyVault?: keyVaultConfig, azureStorage ?: AzureStorage) {
+    constructor(operator: KubeflowOperator, nfs?: NFSConfig, keyVault?: keyVaultConfig, azureStorage ?: AzureStorage) {
         this.operator = operator;
-        this.nfs = nfs;
-        this.kubernetesServer = kubernetesServer;
+        this.nfs = nfs;        
         this.keyVault = keyVault;
         this.azureStorage = azureStorage;
     }

tools/nni_cmd/config_schema.py

@@ -139,8 +139,7 @@ kubeflow_config_schema = {
         'nfs': {
             'server': str,
             'path': str
-        },
-        Optional('kubernetesServer'): str
+        }
     },{
         'operator': Or('tf-operator', 'mxnet-operator', 'pytorch-operator'),
         'keyVault': {