Provision SSH keys that are stored in the PostgreSQL database to the user's namespace in a known to devworkspace-controller format

[skabashnyuk]

Is your task related to a problem? Please describe

The goal of this task is to mount existing SSH keys that used to be mounted in Che7 workspaces to devworkspaces.
See more about format @JPinkney 's comment devfile/devworkspace-operator#613 (comment)

Describe the solution you'd like

Implement new NamespaceConfigurator. in such a form

cat > /tmp/gitconfig <<EOF
host *
  IdentityFile /.ssh/id_rsa
  StrictHostKeyChecking = no
EOF

kubectl create secret generic git-ssh-key \
  --from-file=id_rsa=/path/to/private-key \
  --from-file=id_rsa.pub=/path/to/public-key \
  --from-file=config=/tmp/gitconfig

kubectl patch secret git-ssh-key --type merge -p \
  '{"metadata": {
     "labels": {
        "controller.devfile.io/mount-to-devworkspace": "true",
        "controller.devfile.io/watch-secret": "true"
      }, 
      "annotations": {
        "controller.devfile.io/mount-path": "/.ssh/"
      }
    }
  }'

Describe alternatives you've considered

No response

Additional context

devfile/devworkspace-operator#613