Merge pull request #37635 from T-Lakshmi/k8s-punctuation

Rephrasing the definition of etcd under Glossary

Author: k8s-ci-robot

content/en/docs/reference/glossary/etcd.md

@@ -4,7 +4,7 @@ id: etcd
 date: 2018-04-12
 full_link: /docs/tasks/administer-cluster/configure-upgrade-etcd/
 short_description: >
-  Consistent and highly-available key value store used as Kubernetes' backing store for all cluster data.
+  Consistent and highly-available key value store used as backing store of Kubernetes for all cluster data.
 
 aka: 
 tags: