Describe the issue:
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Fix typo in planning guide under the infrastructure requirements for Microsoft Azure

Suggestions for improvement:
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~~~
Supports internal Red Hat OpenShift Data Foundation clusters only.

An internal cluster must meet both, storage device requirements and have a storage class that provides, an zzure disk via the azure-disk provisioner.
~~~

In the above section, there is a typo "zzure" it should be "azure"

Document URL:
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https://access.redhat.com/documentation/en-us/red_hat_openshift_data_foundation/4.15/html-single/planning_your_deployment/index#microsoft_azure

Chapter/Section Number and Title:
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Chapter 7. Infrastructure requirements - 7.1.4. Microsoft Azure

Product Version:
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4.15

Any other versions of this document that also needs this update:
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4.14, 4.13, 4.12