Description of problem:
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gluster-inventory.yml file is provided as sample inventory file for the customers to create a new inventory file looking at the example inventory file components.

This file is updated for RHHI-V 1.8, the current documentation in 'Automating RHHI deployment' docbook needs to be updated
Chapter 4 in the doc - https://access.redhat.com/documentation/en-us/red_hat_hyperconverged_infrastructure_for_virtualization/1.7/html-single/automating_rhhi_for_virtualization_deployment/index#setting-deployment-variables

Version-Release number of selected component (if applicable):
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Automating RHHI deployment for 1.8

Expected results:
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Update the description of sample inventory file.