fix: syntax error on workflows/docker-image.yml (4/?)

.github/workflows/docker-image.yml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-22.04
     steps:
       - name: Add private key to SSH_AUTH_SOCK
-        run:
+        run: |
           ## https://stackoverflow.com/questions/70507811/invalid-empty-ssh-agent-socket-make-sure-ssh-auth-sock-is-set-how-to-set-ssh-au
           ##
 	  ## Install ssh-agent if not already installed, it is required by Docker.