The operational level command "clear system commit" will clear a pending scheduled commit.
I thought it would work on a commit confirmed but it does not. So there is no way to clear the timer. It makes some sense in that by letting it expire you are just "undoing" your work.
However if you are ok with your changes and just want to push the timer forward and not have another rollback created you can issue the "commit check" command which stops the timer and does the confirmation step also without incrementing your configs.