Another permission fix attempt.

@@ -20,7 +20,6 @@ data:
   clone-start-of-day: |
     #!/bin/sh
     set -ex
-    chmod 600 $HOME/.ssh/config
     # FIXME: don't hard-code this.
     ls -alR $HOME
     git clone git@gitlab.brainfood.com:brainfood/k8s-start-of-day.git /tmp/git-storage/k8s-start-of-day
@@ -74,6 +73,7 @@ spec:
             - name: cluster-ssh
               mountPath: /tmp/cluster-home/.ssh/config
               subPath: SSH_CONFIG
+              mode: 600
             - name: git-storage
               mountPath: /tmp/git-storage
           command: ["/tmp/k8s-bootstrap-scripts/clone-start-of-day"]