Fix some misspellings of 'Kubernetes'. (#614)

Author: collinfunk

content/operate/kubernetes/recommendations/persistent-volumes.md

@@ -33,7 +33,7 @@ spec should include a *persistentSpec* section, in the
 Persistence storage is a requirement for production deployments.
 
 {{< note >}}
-For **production deployments** of Redis Enterprise Cluster on Kubenetes,
+For **production deployments** of Redis Enterprise Cluster on Kubernetes,
 the Redis Enterprise Cluster (REC) must be deployed with persistence enabled.
 The REC deployment files in the [Kubernetes documentation](https://github.com/RedisLabs/redis-enterprise-k8s-docs) contain this declaration by default.
 {{< /note >}}
@@ -53,7 +53,7 @@ Persistent volume claims can be expanded, but not reduced after creation. See [E
 
 {{< note >}}
 We recommend that you omit the volumeSize definition from the REC declaration
-so that the Redis Enterprise Cluster deployment on Kubenetes use the default volume size.
+so that the Redis Enterprise Cluster deployment on Kubernetes use the default volume size.
 {{< /note >}}
 
 ## Storage class name