redis-cli avoids saving sensitive commands in it's history (doesn't
persist them to the history file).
this means that if you had a typo and you wanna re-run the command, you
can't easily do that.
This PR changes that to keep an in-memory history of all the redacted
commands, and just
not persist them to disk. This way we would be able to press the up
arrow and
re-try the command freely, and it'll just not survive a redis-cli
restart.