message: Update validator_onboarding_hard_mode.md
diff: @@ -163,8 +163,7 @@ ol restore
  **note**: temporarily: as of v4.2.8 you'll need to increase your host's file descriptors. Fix is in the works. For now:
  run this before starting your `tmux` session.
  ```
  -# increase file d
  -escriptors
  +# increase file descriptors
  ulimit -n 100000
  # check that they have been increased
  ulimit -n
  