Parallel. The following is from the instruction manual for the Auber 2362 PID:
"4.3 Output connection
Two control output options are offered by this controller. (1) The SSR control
output provides an 8V DC signal that can control up to 4 SSRs in parallel."
So wire the PID output (from terminals 6 & 7) in parallel to the SSR's.
Wire them in parallel so both SSR's get the same voltage. I'm assuming that the PID has sufficient current capacity for this application since the SSR requires very little current.