Update kubeadm-upgrade.md

Add trivial copyedit to check Netlify settings

content/en/docs/reference/setup-tools/kubeadm/kubeadm-upgrade.md

@@ -17,7 +17,7 @@ cluster if necessary.
 ## kubeadm upgrade guidance
 
 Every upgrade process might be a bit different, so we've documented each minor upgrade process individually.
-Please check these documents out for more detailed how-to-upgrade guidance:
+For more detailed how-to-upgrade guidance for each version, see the following resources:
 
  * [1.6 to 1.7 upgrades](/docs/tasks/administer-cluster/kubeadm-upgrade-1-7/)
  * [1.7.x to 1.7.y upgrades](/docs/tasks/administer-cluster/kubeadm-upgrade-1-8/)