fixed offline inj issues and added request_disk

Offline dags using the o4-online-dev branch were failing (= lacking sim_inspiral tables) due to the injection file not being given to --injection-file but instead being given to --injections. This MR fixes the bug in gstlal-inspiral/python/dags/layers/inspiral.py. It also adds request_disk in the submit files when the dags are generated.