Update postgresql deployment documentation

This PR fixes spelling mistake in the command and add information
about requirement of funcional storage class.

documentation/latest/gsg/ocp.md

@@ -50,9 +50,13 @@ git clone {{ page.parodos.git_repo }} -b {{ page.parodos.git_branch }}
 
 ### Installing Parodos
 
+Before appling the manifests please make sure you have a strageclass configured
+and set as default. It is needed to bind persistent volume claim used by
+postgresql.
+
 ```bash
 cd parodos
-kubectl kustomize hack/manifests/openshift/ | kubecl apply -f -
+kubectl kustomize hack/manifests/openshift/ | kubectl apply -f -
 ```
 
 This will install all Parodos microservices on top of Openshift, where the