Create an informative issue (See each section, incomplete templates/issues won't be triaged)

We had previously decided to deprecate the Gatekeeper Operator.  We decided during the ACM 2.8 release that we would not deprecate the Gatekeeper Operator.  We released a new version during 2.9 that is supported and we want to make sure the documenation reflects that gatekeeper is supported and not deprecated. 

Please remove the deprecation notice for Gatekeeper.

https://access.redhat.com/documentation/en-us/red_hat_advanced_cluster_management_for_kubernetes/2.9/html/release_notes/release-notes#deprecations

The deprecation notice appears in the 2.8 and 2.7 documentation also, please remove it there as well.

Please note there are some deprecation notices around the policy for gatekeeper that need to be removed as well.  See section:

https://access.redhat.com/documentation/en-us/red_hat_advanced_cluster_management_for_kubernetes/2.9/html/governance/governance#install-gatekeeper-operator-policy

Describe the changes in the doc and link to your dev story

Provide info for the following steps:

1. - [x] Mandatory Add the required version to the Fix version/s field.

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

      - [ ] New topic in an existing section or new section
      - [x] Update to an existing topic

3. - [x] Mandatory for GA content:
            
     The 2.10 release will include another new release of the Gatekeeper Operator.

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

This is a bug that we caused by changing our minds on the deprecation.  Please let me know if you have any additional questions.

Thanks!