kubeadm: fix godocs indentation for v1beta1

cmd/kubeadm/app/apis/kubeadm/v1beta1/doc.go

@@ -22,7 +22,7 @@ limitations under the License.
 // Package v1beta1 defines the v1beta1 version of the kubeadm config file format.
 // This version graduates the kubeadm config to BETA and is a big step towards GA.
 //
-// A list of changes since v1alpha3:
+//A list of changes since v1alpha3:
 //	- "apiServerEndpoint" in InitConfiguration was renamed to "localAPIServerEndpoint" for better clarity of what the field
 //	represents.
 //	- Common fields in ClusterConfiguration such as "*extraArgs" and "*extraVolumes" for control plane components are now moved
@@ -30,6 +30,8 @@ limitations under the License.
 //	- "auditPolicy" was removed from ClusterConfiguration. Please use "extraArgs" in "apiServer" to configure this feature instead.
 //	- "unifiedControlPlaneImage" in ClusterConfiguration was changed to a boolean field called "useHyperKubeImage".
 //	- ClusterConfiguration now has a "dns" field which can be used to select and configure the cluster DNS addon.
+//	- "featureGates" still exists under ClusterConfiguration, but there are no supported feature gates in 1.13.
+//	See the Kubernetes 1.13 changelog for further details.
 //	- Both "localEtcd" and "dns" configurations now support custom image repositories.
 //	- the "controlPlane*" related fields in JoinConfiguration were refactored into a sub structure.
 //	- "clusterName" was removed from JoinConfiguration and the name is now fetched from the existing cluster.