Starting from 6.2, after ACL SETUSER user reset, the user
will carry the sanitize-payload flag. It was added in #7807,
and then ACL SETUSER reset is inconsistent with default
newly created user which missing sanitize-payload flag.
Same as `off` and `on` these two bits are mutually exclusive,
the default created user needs to have sanitize-payload flag.
Adds USER_FLAG_SANITIZE_PAYLOAD flag to ACLCreateUser.
Note that the bug don't have any real implications,
since the code in rdb.c (rdbLoadObject) checks for
`USER_FLAG_SANITIZE_PAYLOAD_SKIP`, so the fact that
`USER_FLAG_SANITIZE_PAYLOAD` is missing doesn't really matters.
Added tests to make sure it won't be broken in the future,
and updated the comment in ACLSetUser and redis.conf
bb6513cbba