Improve setup of a review app database

Author: mphasize

.github/workflows/deploy-preview.yml

@@ -56,8 +56,8 @@ jobs:
         # see https://blog.benoitblanchon.fr/github-action-run-ssh-commands/
         run: |
           ssh -t preview "postgres:clone certificates-db ${REVIEW_APP_NAME}-db"
+          ssh -t preview "postgres:unlink certificates-db ${REVIEW_APP_NAME}"          
           ssh -t preview "postgres:link ${REVIEW_APP_NAME}-db $REVIEW_APP_NAME"
-          ssh -t preview "postgres:promote ${REVIEW_APP_NAME}-db $REVIEW_APP_NAME"
         env:
           REVIEW_APP_NAME: pre-${{ github.event.pull_request.number }}