Revert "install: do not create the ${GITLAB_DATA_DIR}/.ssh directory, its created in the init script"

This reverts commit 8aba575f89cde29a03cc3537a7f99799ceaf8b07.
Revert "install: do not create the ${GITLAB_DATA_DIR}"

This reverts commit 45edbf3469dd96fd7914a5c10a61a984b77cc2b8.