Apply templates to all concepts and tasks to fix double bullets in TOC (#9149)

* Apply concept template to fix double bullet issue.

* Apply concept template

* Apply templates to tasks

content/en/docs/concepts/storage/storage-classes.md

@@ -5,15 +5,22 @@ reviewers:
 - thockin
 - msau42
 title: Storage Classes
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 weight: 30
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 This document describes the concept of `StorageClass` in Kubernetes. Familiarity
 with [volumes](/docs/concepts/storage/volumes/) and
 [persistent volumes](/docs/concepts/storage/persistent-volumes) is suggested.
 
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 ## Introduction
 
 A `StorageClass` provides a way for administrators to describe the "classes" of
@@ -670,3 +677,5 @@ specified by the `WaitForFirstConsumer` volume binding mode.
 Delaying volume binding allows the scheduler to consider all of a pod's
 scheduling constraints when choosing an appropriate PersistentVolume for a
 PersistentVolumeClaim.
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