Remove sllh computation from `petab_objective.simulate_petab` (#1498)
Remove sllh computation from `petab_objective.simulate_petab` (#1498)

* fix aggregate_sllh for petab objectives

* extend benchmark tests to check gradient of simulate_petab

* fixup

* fix by removing functionality

* fixup

* cleanup

* cleanup
FFroehlich/AMICI,FFroehlich/AMICI,FFroehlich/AMICI,FFroehlich/AMICI