Merge pull request #31470 from caesarxuchao/regenerate-release-1-4

Automatic merge from submit-queue

Fix missing expansion files in clientset release 1.4

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**What this PR does / why we need it**:
Fix missing expansion files in clientset release 1.4;
Update the client-gen tool to automatically update generated_expansion.go;
Update the readme to document the best practice of using client-gen.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #

https://github.com/kubernetes/kubernetes/issues/29698#issuecomment-241315798


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**Release note**:
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cc @lavalamp @krousey @mbohlool

federation/client/clientset_generated/federation_internalclientset/typed/core/unversioned/generated_expansion.go

@@ -16,8 +16,8 @@ limitations under the License.
 
 package unversioned
 
-type SecretExpansion interface{}
-
 type EventExpansion interface{}
 
+type SecretExpansion interface{}
+
 type ServiceExpansion interface{}

federation/client/clientset_generated/federation_internalclientset/typed/extensions/unversioned/generated_expansion.go

@@ -16,6 +16,6 @@ limitations under the License.
 
 package unversioned
 
-type ReplicaSetExpansion interface{}
-
 type IngressExpansion interface{}
+
+type ReplicaSetExpansion interface{}

federation/client/clientset_generated/federation_release_1_4/typed/core/v1/generated_expansion.go

@@ -16,8 +16,8 @@ limitations under the License.
 
 package v1
 
-type SecretExpansion interface{}
-
 type EventExpansion interface{}
 
+type SecretExpansion interface{}
+
 type ServiceExpansion interface{}

federation/client/clientset_generated/federation_release_1_4/typed/extensions/v1beta1/generated_expansion.go

@@ -16,6 +16,6 @@ limitations under the License.
 
 package v1beta1
 
-type ReplicaSetExpansion interface{}
-
 type IngressExpansion interface{}
+
+type ReplicaSetExpansion interface{}