Additions to cover story [ACM 3842]

1. Prerequisite: Start with what we have

• In section "Creating an Automation Template", we need to add an additional step after current step #4 ("Select the credential...").

• This step should mention that once a credential has been selected, the user can select an Ansible inventory to use for all of the jobs.

• Link to the doc -> https://access.redhat.com/documentation/en-us/red_hat_advanced_cluster_management_for_kubernetes/2.7/html/clusters/cluster_mce_overview#ansible-template-create

Provide info for the following steps:

1. - [ ] *Mandatory* Choose the documentation release (Published releases are refreshed ~weekly after publication). 
     
      - [x] ACM 2.8 (upcoming release)
      - [x] MCE 2.3 (upcoming release)
   

2. - [ ] *Mandatory* Choose the type of documentation change.

      - [x] Update to an existing topic

3. - [ ] *Mandatory for bugs:* What is the diff? Clearly define what the problem is, what the change is, and link to the current documentation:

4. - [ ] *Mandatory for GA content:*
            
       - [ ] Add steps and/or other important conceptual information here: 
       
            
       - [ ] Add *Required access level* for the user to complete the task here:
       

       - [ ] Add verification at the end of the task, how does the user verify success (a command to run or a result to see?)
     
     
       - [ ] Add link to dev story here:

   - *Errata release note* version, this is NOT for regular refreshes: 
      (published with Errata release)
  
      - [ ] ACM 2.4.x
      - [ ] ACM 2.5.x
      - [ ] ACM 2.6.x
      - [ ] MCE 2.0.x
      - [ ] MCE 2.1.x

5. *Optional:* Get back to issue templates to create more issues for the doc team: https://github.com/open-cluster-management/backlog/issues/new/choose