Backport of [NET-6249] Add templated policies description into release/1.17.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #19735 to be assessed for backporting due to the inclusion of the label backport/1.17.

The below text is copied from the body of the original PR.

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Description

• Though the templated policy names are self explanatory for the most part, we thought it'd be a good idea to have a description that allows to make it easier for someone not as familiar with Consul to use them.
• This PR adds description to the templated policies

Testing & Reproduction steps

consul acl templated-policy read -name "builtin/dns"

Name:            builtin/dns
Description:     Gives the token or role permissions for the Consul DNS to query services in the network.
Input variables: None
Example usage:
	consul acl token create -templated-policy builtin/dns

PR Checklist

• updated test coverage
• appropriate backport labels added
• not a security concern

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Overview of commits

• 5cf44be

[github-team-consul-core-pr-approver]

Auto approved Consul Bot automated PR