contrib: dracut: zfs-{rollback,snapshot}-bootfs: order after key loading

This fixes at least one race I got with an encrypted root

Upstream-commit: 6ebdb0b20de444f69404c265352a27e1b4e49b93
Upstream-commit: b8d9679f3644c813f7aa6db5b9c978b88758049a
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes #13291