multi: remove total timer reset in file_do() while fetching file://
The total timer is properly reset in MSTATE_INIT. MSTATE_CONNECT starts
with resetting the timer that is a start point for further multi states.
If file://, MSTATE_DO calls file_do() that should not reset the total
timer. Otherwise, the total time is always less than the pre-transfer
and the start transfer times.
Closes #12682