Gen2 Content Update: branch auto disconnect button should be removed until GA

**Describe the content issue**:
The branch auto disconnect button is not available yet and should be removed from this page. The video also contains an image of this feature that should be removed.

**URL page where content issue is**:
https://docs.amplify.aws/gen2/deploy-and-host/fullstack-branching/branch-deployments/#set-up-feature-branch-deployments